Question

Can someone help with that?

if x+y=2, calculate:
P=4x (x-3)+4y(y-3)+8xy​

Answer 1

Explanation:

P = 4x(x - 3) + 4y(y - 3) + 8xy

= 4x² - 12x + 4y² - 12y + 8xy

= (4x² + 8xy + 4y²) - (12x + 12y)

= 4(x² + 2xy + y²) - 12(x + y)

= 4(x + y)² - 12(x + y)

x+y =2 ⇒ P = 4.2² - 12.2 = 16 - 24 = -8