Question

1) ax+ay+bx+by onde a+b=15 e x+y=6

2)sabendo que xy=15 calcule (x-y)²-(x+y)²

Answer 1

Olá Sky

1)

ax + ay + bx + by = a*(x + y) + b*(x + y) = (a + b)*(x + y) = 15*6 = 90

2)

(x - y)² - (x + y)² = 

x² - 2xy + y² - x² - 2xy - y² = -4xy = -4*15 = -60 

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