Thread: I need help on factoring these.

By factoring using the zero product principal.
x + 1 = 9^3 + 9^2

9y^3+8=4y+18y^2

4x^3 - 12x^2 = 9x -27

Eeeep. I hate Algebra. ;c

Originally Posted by Maditay

9y^3+8=4y+18y^2

A hint on this one:
9y^3 - 4y - 18y^2 + 8 = 0
y(9y^2 - 4) - 2(9y^2 - 4) = 0

Did you follow that? Can you finish it?

If not, almost impossible to classroom-teach here.

Originally Posted by Maditay

By factoring using the zero product principal.
x + 1 = 9^3 + 9^2

9y^3+8=4y+18y^2

4x^3 - 12x^2 = 9x -27

Eeeep. I hate Algebra. ;c

here is link which may help you
Factor theorem - Wikipedia, the free encyclopedia

Originally Posted by Maditay

By factoring using the zero product principal.
x + 1 = 9^3 + 9^2

9y^3+8=4y+18y^2

4x^3 - 12x^2 = 9x -27

Eeeep. I hate Algebra. ;c

Hi Maditay,

That first one doesn't make a lot of sense. Turns out to be x = 809. What's to factor? It's linear.

The last one can be grouped to factor. Bring everything to the left side and set equal to zero.

$\displaystyle 4x^3-12x-9x+27=0$

$\displaystyle 4x^2(x-3)-9(x-3)=0$

Finish up by factoring out the common factor of (x - 3), and then use your zero product property.