Question

If x - y = 12 and x - y = 4, what is the value of x + 2xy + y??​

Answer 1

H. 9

Explanation:

Using the difference of 2 squares formula, we get (x - y)(x + y)=12

Divide each side by x - y: x + y = 12/(x - y)

But x - y = 4, so replace x - y by 4: x + y = 12/4 = 3

Because x^2 + 2xy + y^2 = (x + y)^2, so we take our equation exponent by 2:

(x + y)^2 = 3^2 = 9

x^2 + 2xy + y^2 = 9