Question

x elavado a 2 - 4x - 5 = 0

Answer 1

x^2-4x-5=0
delta=b^2-4ac
delta=(-4)^2-4.1.(-5)
delta=16+20
delta=36
x=-b-/+ raiz de delta/2a
x=-(-4)-6/2.1
x=4-6/2
x=-2/2
x=-1
x=-(-4)+6/2.1
x=4+6/2
x=10/2
x=5
S={-1, 5}