#Hello! I need help with my grade 8 algebra honors review guide.

64 messages · Page 1 of 1 (latest)

vague juncoBOT
steady otter
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Alright

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Try factoring out 5mn first and then using difference of squares.

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You don't really have to, 5mn goes into both terms.

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Yep

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I mean you do have to check for gcf but it's pretty easy to do.

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Yes it's correct.

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Ok so your two terms that can't be combined are 45m^3n and 5mn, correct?

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Let's look at the coefficients first.

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What is the gcf of 5 and 45?

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Correct

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Next, let's look at the variable m

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What's the gcf of m^3 and m?

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Yep

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Finally, what is the gcf of n and n?

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So now we multiply those together, which gives us an overall gcf of 5mn.

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Have you learned factoring yet?

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Okay so here we factor 5mn out of 45m^3n-5mn, which brings us to 5mn(9m^2-1).

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At this point all that's left is to use difference of squares.

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Do you get it now?

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Ok

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Correct

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Does that help?

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Always look for factoring opportunities

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I don't know how to define that well for you, but it's basically pulling a factor out of a polynomial to simplify it.

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Guess what grade I'm in (just for fun)

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Nope 8th grade lol

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Ty

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Sure

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Send a screenshot of your problem, work and answer

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Yep

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Don't forget that you are factoring x out of x^3

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So the 4 in the parentheses would be 4x^2

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No...so if you are factoring x out of x^3, then you are basically dividing x^3 by x, but we can't call it dividing because x could be 0.

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Yes

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Essentially

steady otter
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x times x^2, but yes

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I think you understand now 👍

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Yes 👍

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You have it now

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Ok

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Yes

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Try to make the expression into a square

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Find the gcf for the whole expression

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Yes, but there are three terms so factoring two won't let you factor anything else...let's try it your way just to see what happens

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Yes

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The problem with factoring 16 is that it then becomes x^2+16(x^2+4x), and we can't make any more progress.

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By factoring x, we make it x(x^2+16x+64), which is a square.

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Here, we can further factor it into x(x+8)^2

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Try another trinomial on your own

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Oh ok

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Umm...

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Idk how to help with that, let me think of a solution

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Yes, in the meantime maybe you can list factor pairs of 64 and pairs of numbers that add up to 16, and find the overlapping pairs.

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Oh that's really soon

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Given enough time you will memorize these combinations but idk how you would learn it in 2 days

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Maybe ask your teacher if you can use it? I'm not sure what you can do otherwise.

steady otter
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Yes, that is true, but is also a problem in your case.

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Yes

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It's still difference of squares so yea

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Yes, it's not factoring...it's difference of squares, which is why you don't use gcf.

keen yacht
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.close