3. Express y= -2x^2 + 28x-26 in factored form

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

help plz!!!

3. Express y= -2x^2 + 28x-26 in factored form

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

help plz!!!

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

help plz!!!

- stapel_eliz
**Posts:**1686**Joined:**Mon Dec 08, 2008 4:22 pm-
**Contact:**

Where are you stuck? Which part is causing you difficulty?

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?

To put this into "y = a(x - h)^{2} + k" form, you'll need to **complete the square**.

If you get stuck, please reply showing all your steps. Thank you!

buddy wrote:3. Express y= -2x^2 + 28x-26 in factored form

What

Then

buddy wrote:6. Express y= -9x^2 + 72x +81 in vertex form

To put this into "y = a(x - h)

If you get stuck, please reply showing all your steps. Thank you!

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?

4. -9(x^2+72x)+81 but i dont knoe what to do next?

- stapel_eliz
**Posts:**1686**Joined:**Mon Dec 08, 2008 4:22 pm-
**Contact:**

buddy wrote: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

. . . . .-2x

. . . . .28x = -2(-14x)

. . . . .-26 = -2(13)

So what should you get, when you take a -2 out of -2x

buddy wrote: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...?

i figured t out thnx