#Analytical geometry

43 messages · Page 1 of 1 (latest)

stark mesa
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A(1, 4k-1), B(6, -3), C(-5, 3k+7) if the given points are linear, what's the value of k?

waxen dagger
stark mesa
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wait what formula

waxen dagger
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That 1/2 |x1(y2 - y3....|

stark mesa
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but the A B C points are not a part of a triangle

waxen dagger
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If the points are collinear, their area would be 0.

stark mesa
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they all lay on the same line

waxen dagger
stark mesa
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doesnt have an area

waxen dagger
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agreed?

stark mesa
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yes

waxen dagger
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If the 3 points are not collinear

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they must form a triangle, agreed?

stark mesa
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yes

waxen dagger
stark mesa
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do i just have to plug in the x and y coordinates to the formula

waxen dagger
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Yeah.

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You'll get an equation.

stark mesa
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yeah wow

waxen dagger
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with k in it.

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and then solve for k.

stark mesa
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if i did no mistakes it should be 28/29

waxen dagger
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,w det((1,2),(3,4))

tropic surgeBOT
waxen dagger
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,w 1/2*det((1,4k-1),(6,-3),(-5,3k+7))=0

tropic surgeBOT
waxen dagger
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,w det((1,4k-1),(6,-3),(-5,3k+7))=0

tropic surgeBOT
waxen dagger
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,w det((1,4k-1),(6,-3),(-5,3k+7))

tropic surgeBOT
waxen dagger
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oh

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,w 1/2*det((1,4k-1,1),(6,-3,1),(-5,3k+7,1))=0

tropic surgeBOT
waxen dagger
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@stark mesa You are right.

stable steppe
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Can't you just find the slope between the points and set them equal to each other?

image.png
waxen dagger
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My mind didn't see that for some weird reason :p

stark mesa
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both solutions require only 1 equation anyways

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thank you all for helping out