Question

solucao de (x+3).(x-5)=0

Answer 1

(x+3).(x-5)
x^2-5x+3x-15
x^2-2x-15=0
delta=b^2-4ac
delta=(-2)^2-4.1.(-15)
delta=4+60
delta=64
x=-b-/+ raiz de delta/2a
x=-(-2)-8/2.1
x=2-8/2
x=-6/2
x=-3
x=-(-2)+8/2.1
x=2+8/2
x=10/2
x=5
S=(-3, 5)