## Express y=-2x^2+28x-26 in factored form, y=-9x^2+72+81 in ve

Simplificatation, evaluation, linear equations, linear graphs, linear inequalities, basic word problems, etc.
buddy
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### Express y=-2x^2+28x-26 in factored form, y=-9x^2+72+81 in ve

3. Express y= -2x^2 + 28x-26 in factored form
6. Express y= -9x^2 + 72x +81 in vertex form

help plz!!!

stapel_eliz
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Where are you stuck? Which part is causing you difficulty?
3. Express y= -2x^2 + 28x-26 in factored form
What factor is common between -2, 28, and -26? (Yes, take the "minus" sign, too; it'll make the rest easier.)

Then factor the remaining quadratic. Hint: What factors of 13 add up to -14?
6. Express y= -9x^2 + 72x +81 in vertex form
To put this into "y = a(x - h)2 + k" form, you'll need to complete the square.

buddy
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### Re: Express y=-2x^2+28x-26 in factored form, y=-9x^2+72+81 in ve

3. -2 is the common factor? so i get -2(x^2+14-13), but i cant factor this?
4. -9(x^2+72x)+81 but i dont knoe what to do next?

stapel_eliz
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Joined: Mon Dec 08, 2008 4:22 pm
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### Re: Express y=-2x^2+28x-26 in factored form, y=-9x^2+72+81 in ve

3. -2 is the common factor? so i get -2(x^2+14-13), but i cant factor this?
Try slowing down and doing your steps more explicitly when you factor. Inside the parentheses, you've dropped an "x" and have lost track of some signs!

. . . . .-2x2 = -2(x2)
. . . . .28x = -2(-14x)
. . . . .-26 = -2(13)

So what should you get, when you take a -2 out of -2x2 + 28x - 26?
4. -9(x^2+72x)+81 but i dont knoe what to do next?
First, check your factorization. It doesn't look like you took the -9 out of the 72x in the middle...?

buddy
Posts: 197
Joined: Sun Feb 22, 2009 10:05 pm
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### Re: Express y=-2x^2+28x-26 in factored form, y=-9x^2+72+81 in ve

i figured t out thnx