Question

Factor completely.
4y^2-36y+72

Answer 1

hint:

4y^2-36y+72 = 4(y^2 - 9y + 8)

Answer 2

oops

4y^2-36y+72 = 4(y^2 - 9y + 18)

Answer 3

first see if everything is divisible by 4
then try the rest

Answer 4

Would it be something like:
(4y-6+?)(4y-6y+?)

Answer 5

Everything is divisible by 4!

Answer 6

try to factor y^2 - 9y + 18

Answer 7

when you factor that 4 out, you can temporarily ignore it

Answer 8

is it (y^2-9y+18) ?? or would i have to divide that into two?

Answer 9

find two numbers that multiply to 18 and add to -9

Answer 10

6 and 3

Answer 11

close

Answer 12

-6 and -3

Answer 13

-6 and -3

Answer 14

-6 plus -3 = -9

-6 times -3 = 18

Answer 15

it's always good to check

Answer 16

so that means y^2 - 9y + 18 factors to (y - 6)(y - 3)

notice how we have the -6 and -3 in the factorization

Answer 17

Thank you for the help. It so much clearer now!

Answer 18

so you should have 4(y - 6)(y - 3) as your final answer

don't forget that 4 we pulled out for a short while

Answer 19

you're welcome