Question

sabendo que yx= -20 e x²+y²= 41 , o valor de y-x e ? A) 5 B)-4 C)9 D)-8

Answer 1

(x-y)² = x²+y² - 2.xy

(x-y)² = 41 - 2.(-20)

(x-y)² = 41 + 40

(x-y)² = 81

(x-y) = √81

x-y = 9 ✓