still need help but diff question | Mathematics | Page 1

fading gulch Jun 20, 2023, 8:47 PM

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just got no clue how to do it

mighty vesselBOT Jun 20, 2023, 8:47 PM

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fading gulch just got no clue how to do it

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Wait patiently for a helper to come along.
Once someone helps you, say thank you and close the thread with:

+close

Feel free to nominate the person for helper of the week in #helper-nominations

rigid phoenix Jun 20, 2023, 8:53 PM

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Multiply #2 by -3 to cancel y

fading gulch Jun 20, 2023, 8:54 PM

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-18x=4

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but then what

rigid phoenix Jun 20, 2023, 8:55 PM

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What

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Check your multiplication or addition again

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For both x and constant

fading gulch Jun 20, 2023, 8:56 PM

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6x-3= - 18

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7x-3=4

rigid phoenix Jun 20, 2023, 8:56 PM

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What

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The second equation becomes -3y - 18x = -21

fading gulch Jun 20, 2023, 8:57 PM

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o

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having a slower moment

grand plinth Jun 20, 2023, 9:00 PM

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The solution to the system of equations is x = 7/6 and y = 0.@fading gulch

rigid phoenix Jun 20, 2023, 9:01 PM

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That is wrong though

raw sluice Jun 20, 2023, 9:01 PM

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grand plinth The solution to the system of equations is x = 7/6 and y = 0.<@70873133686888869...

3 (0) + 8 (7/6) = 28/3 ≠ 16
it's generally considered better to help somebody find the answer, rather than just giving it to them (teach a man to fish...)

grand plinth Jun 20, 2023, 9:02 PM

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If he wants explenation he could ask me

rigid phoenix Jun 20, 2023, 9:02 PM

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But the thing is wrong

grand plinth Jun 20, 2023, 9:02 PM

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My bad then

fading gulch Jun 20, 2023, 9:03 PM

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rigid phoenix The second equation becomes -3y - 18x = -21

what do i do after that

rigid phoenix Jun 20, 2023, 9:03 PM

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Cancel the y

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Add the equations

fading gulch Jun 20, 2023, 9:03 PM

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so y become 0 overall

timid otter Jun 20, 2023, 9:04 PM

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that's not a good way of thinking of it

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Your goal is to find what the values of x and y that satify both equation 1 and 2

fading gulch Jun 20, 2023, 9:04 PM

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and -10x=-5?

timid otter Jun 20, 2023, 9:04 PM

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to do that, you can find the value of x first

rigid phoenix Jun 20, 2023, 9:04 PM

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Yes

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Divide by -10

timid otter Jun 20, 2023, 9:05 PM

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by multiplying the second equation by -3 and then adding equation 2 to 1

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you'll be left with an equation of only x, then solve for x, plug that x into either equation 1 or 2 and solve for y

fading gulch Jun 20, 2023, 9:06 PM

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when i do -5/-10 it give me -15 that right or am i just gone??

timid otter Jun 20, 2023, 9:06 PM

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So 3 steps:

isolate for a single variable (x or y)
solve for that variable
plug in that number back into one of the equations and solve for last variable

timid otter Jun 20, 2023, 9:07 PM

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fading gulch when i do -5/-10 it give me -15 that right or am i just gone??

Do you know how to solve this equation -10x = -5?

fading gulch Jun 20, 2023, 9:07 PM

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divide -5 by -10

timid otter Jun 20, 2023, 9:07 PM

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yes and that gives you?

fading gulch Jun 20, 2023, 9:07 PM

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-15

timid otter Jun 20, 2023, 9:08 PM

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no it doesn't.

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you're doing -5 - 10

fading gulch Jun 20, 2023, 9:08 PM

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on phone calc it does

timid otter Jun 20, 2023, 9:08 PM

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don't use a calculator.

fading gulch Jun 20, 2023, 9:08 PM

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0.5

timid otter Jun 20, 2023, 9:08 PM

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so you have x = 0.5 that's correct

fading gulch Jun 20, 2023, 9:08 PM

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yes

timid otter Jun 20, 2023, 9:08 PM

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the next step is to do what?

fading gulch Jun 20, 2023, 9:09 PM

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replace x with 0.5

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and so on

timid otter Jun 20, 2023, 9:09 PM

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go for it.

fading gulch Jun 20, 2023, 9:09 PM

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y=4

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i take it id do this question the same way?

timid otter Jun 20, 2023, 9:11 PM

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#1120817322391765112 message

fading gulch Jun 20, 2023, 9:14 PM

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uhhhhhh

rigid phoenix Jun 20, 2023, 9:16 PM

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Yes

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Multiply the first by -2

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To cancel the x

grand plinth Jun 20, 2023, 9:17 PM

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The slope-intercept form of the line whose equation is 3y - 2x = 8 is y = (2/3)x + (8/3).

fading gulch Jun 20, 2023, 9:20 PM

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-6y+2x=-16

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?

rigid phoenix Jun 20, 2023, 9:21 PM

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Yes

tropic thorn Jun 20, 2023, 9:21 PM

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fading gulch i take it id do this question the same way?

3y - x = 8 (1)

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5y - 2x = 6 (2)

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(1) x 2

grand plinth Jun 20, 2023, 9:21 PM

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-6y + 2x = -16
-6y = -2x - 16
y = (1/3)x + (8/3)

tropic thorn Jun 20, 2023, 9:21 PM

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6y - 2x = 16 (3)

rigid phoenix Jun 20, 2023, 9:21 PM

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What

timid otter Jun 20, 2023, 9:21 PM

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yikes

fading gulch Jun 20, 2023, 9:22 PM

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my brain

grand plinth Jun 20, 2023, 9:22 PM

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fading gulch my brain

@fading gulch 😭

timid otter Jun 20, 2023, 9:22 PM

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why are you guys doing his homework for him lol

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let the guy solve it himself

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you're not helping giving all the answers away

tropic thorn Jun 20, 2023, 9:22 PM

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im tryna show him the right working out

fading gulch Jun 20, 2023, 9:22 PM

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timid otter you're not helping giving all the answers away

innit i got another 4 of the questions after

rigid phoenix Jun 20, 2023, 9:23 PM

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Ok anyways

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What can we cancel after we multiply

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?

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The first equation

fading gulch Jun 20, 2023, 9:24 PM

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the 2x

rigid phoenix Jun 20, 2023, 9:24 PM

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Yea

fading gulch Jun 20, 2023, 9:24 PM

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my signal died

rigid phoenix Jun 20, 2023, 9:25 PM

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So eliminate that and solve for x and y the rest of the way

fading gulch Jun 20, 2023, 9:25 PM

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ok

tropic thorn Jun 20, 2023, 9:25 PM

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order ur solution like thi

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or somth like this

fading gulch Jun 20, 2023, 9:27 PM

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hmm

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ok

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10f - 9g = 12 (1)
2f +3g = 12 (2)

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(2) x 3

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wait

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no

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6f + 9g =36 (3)

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(3) - (1)

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@tropic thorn am i on right track with this question ( diff one tk before)

tropic thorn Jun 20, 2023, 9:32 PM

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👍

fading gulch Jun 20, 2023, 9:34 PM

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6f + 9g - 10f -9g = 36 - 12

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-4f = 24

fading gulch Jun 20, 2023, 9:34 PM

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tropic thorn 👍

that can’t be right

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someone help

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still need help but diff question

timid otter Jun 20, 2023, 9:42 PM

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$$
10x-9y = 12 \quad (1)\

2x + 3y =12 \quad (2) \

\text{Working with (2) to isolate x} \
2x = 12-3y \
x = 6 - 1.5y \
\text{sub (2) into (1)} \
10(6-1.5y) -9y = 12 \
60-15y - 9y = 12 \
60-12 = 24y \
2 = y
$$

fading gulch Jun 20, 2023, 9:43 PM

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where’d i go wrong?

slender kernelBOT Jun 20, 2023, 9:43 PM

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conquestace
Compile Error! Click the errors reaction for more information.
(You may edit your message to recompile.)

timid otter Jun 20, 2023, 9:43 PM

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I don't know.

timid otter Jun 20, 2023, 9:44 PM

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fading gulch where’d i go wrong?

for one, you're adding equation 1 and 2, but you did 6f-10f

fading gulch Jun 20, 2023, 9:45 PM

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o

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no i did equation 3- 1

timid otter Jun 20, 2023, 9:46 PM

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same with 36-12 when its suppose to be 36+12

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yeah (3) - (1) is : 6f + 9g - (10f-9g) = 36 - 12

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giving you -4f + 18g = 24

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you're suppsoe to do (3) + (1) : 6f + 9g + (10f-9g) = 36+12

fading gulch Jun 20, 2023, 9:48 PM

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oh

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how do i know when to add the equations or subtract?

timid otter Jun 20, 2023, 9:48 PM

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what is ur goal?

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to eliminate a varaible

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that's why it's called elimnination method

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use your head to determine when to add or subtract

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The method I showed was the substitution method, because I isolate for a single variable and then substitute it back into the other equation

tropic thorn Jun 20, 2023, 10:08 PM

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fading gulch -4f = 24

this isn't wrong

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you're on the right track

fading gulch Jun 20, 2023, 10:11 PM

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o

timid otter Jun 20, 2023, 10:13 PM

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fading gulch o

are you sure what you did was right?

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I am pretty sure the answer is f=3 and g =2

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if you do -4f = 24 you get f = -6

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you plug that back into 2 and you get: 2*(-6) + 3g = 12

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g= 8

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but when u put in 10(-4) - 9(8) =/= 12

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I don't know @tropic thorn is trying to do

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troll maybe?

tropic thorn Jun 20, 2023, 10:38 PM

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this is right

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you continue solving

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f = -6

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sub f into (1)

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10f - 9g = 12 (1)

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10 x -6 - 9g = 12

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-60 - 9g = 12

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-9g = 72

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g = -8

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@timid otter

timid otter Jun 20, 2023, 10:39 PM

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okay.

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plug those back into your equations

rigid phoenix Jun 20, 2023, 10:40 PM

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That is wrong

timid otter Jun 20, 2023, 10:40 PM

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and let me know if uget the answer.

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I know 100% f = 3 and g = 2

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lol

rigid phoenix Jun 20, 2023, 10:40 PM

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fading gulch 6f + 9g - 10f -9g = 36 - 12

Where did you get -10f and -12 from

tropic thorn Jun 20, 2023, 10:41 PM

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what

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10 x - 6 - 9 x - 8

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-60 + 72 = 12

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is it not right?

rigid phoenix Jun 20, 2023, 10:42 PM

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It works for one of them

tropic thorn Jun 20, 2023, 10:45 PM

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fading gulch 6f + 9g - 10f -9g = 36 - 12

this step is wrong

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lol mb didn't look at it right

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should be 6f + 9g - 10f + 9g = 36 -12 according to (3) - (1)

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it should be (1) + (3)

#still need help but diff question