Question

88 POINTS!!!!! Multiply:

1. (y−4)2

2. 5(y+4)2

3. (y+4)2

4. 5(y−4)2

Answer 1

Use the distribution method.

1) 2y - 8

2) 10y + 40

3) 2y + 8

4) 10y - 40

The one in the picture simplified is 5/2y + 10

Answer 2

Thus # 2 is correct (5 (y + 4))/2

Explanation:

Simplify the following:

(5 y (y^2 - 16))/(2 y (y - 4))

(5 y (y^2 - 16))/(2 y (y - 4)) = y/y×(5 (y^2 - 16))/(2 (y - 4)) = (5 (y^2 - 16))/(2 (y - 4)):

(5 (y^2 - 16))/(2 (y - 4))

y^2 - 16 = y^2 - 4^2:

(5 (y^2 - 4^2))/(2 (y - 4))

Factor the difference of two squares. y^2 - 4^2 = (y - 4) (y + 4):

(5 (y - 4) (y + 4))/(2 (y - 4))

Cancel terms. (5 (y - 4) (y + 4))/(2 (y - 4)) = (5 (y + 4))/2:

Answer: (5 (y + 4))/2