Question

qual é a raiz real de (x+7) × (-x+11)=0

Answer 1

(x+7) x (-x+11)=0

-x²+11x-7x+77=0

-x²+4x+77=0

Δ=4²-4.-1.77
Δ=16-4.-1.77
Δ=16+308
Δ=324
Δ=√324=18

×'=-4+18/2=7

x''=-4-18/2=-11