# Thread: i need help with these factor problems

1. ## i need help with these factor problems

i need help on factoring these the chapter is called "5-11 using several methods of factoring"

2x^4-162

25z^3-36y^2z

can you show how you did it to

2. Originally Posted by elfen_lied
i need help on factoring these the chapter is called "5-11 using several methods of factoring"

2x^4-162
$\displaystyle 2x^4-162$
$\displaystyle 2(x^2-81)$
$\displaystyle 2(x^2-9^2)$
$\displaystyle 2(x-9)(x+9)$

25z^3-36y^2z
$\displaystyle 25z^3-36y^2z$
$\displaystyle z(25z^2-36y^2)$
$\displaystyle z(5^2z^2-6^2y^2)$
$\displaystyle z[(5z)^2-(6y)^2]$
$\displaystyle z(5z-6y)(5z+6y)$

3. oh and i need help on this problem also

6x^2+22xy-8y^2

edit:and this

x^3-x+6x^2-6

4. Originally Posted by elfen_lied
oh and i need help on this problem also
6x^2+22xy-8y^2
edit:and this
x^3-x+6x^2-6
Hello,

I haven't much time, so I send you only the results:

$\displaystyle 6x^2+22xy-8y^2=6x^2-2xy+24xy-8y^2$ $\displaystyle =2x(3x-y)+8y(3x-y)=(3x-y)(2x+8y)$

$\displaystyle x^3-x+6x^2-6=x(x^2-1)+6(x^2-1)=(x^2-1)(x+6)=(x+1)(x-1)(x+6)$

EB