Question

f(x)=-x^2-8x+20 calcule

Answer 1

Vamos là.

-x² - 8x + 20

a = -1, b = -8, c = 20

delta

d = 64 + 80 = 144

x1 = (8 + 12)/-2 = -10

x2 = (8 - 12)/-2 = 2