Question

Find the unknown:
(-5y-2)^2+11=18

Answer 1

take -1 out from (-5y - 2)^2:

Answer 2

(-1[5y+2])^2 = [5y+2]^2

Answer 3

so now:
[5y+2]^2 = 18 - 11 (move 11 to the right)

Answer 4

(5y+2)^2 = 7
25y + 20y + 4 = 7

Answer 5

move 7 to the left:
25y + 20y +4 -7 = 0
25y + 20y - 3 = 0

Answer 6

Now find discriminant:
D = b^2 - 4ac, where b = 20, a = 25 and c = -3

Answer 7

what did you do with the -1 after you factored it out?

Answer 8

Oh it was inside a square right, so:
(-1[5y+2])^2 = (-1)^2 [5y+2]^2 = 1 * [5y+2]^2 = [5y+2]^2

Answer 9

Oh it was inside a square right, so:
(-1[5y+2])^2 = (-1)^2 [5y+2]^2 = 1 * [5y+2]^2 = [5y+2]^2

Answer 10

sorry for late response, i just keep crashing..

Answer 11

no problem

Answer 12

25y + 20y - 3 = 0
D = b^2 - 4ac, where b = 20, a = 25 and c = -3
D = 400 + 300 = 700

Answer 13

i got it! thanks! :)

Answer 14

okay np.. can you please click on become a fan, thanks!

Answer 15

sure!