Question

x ao quadrado menos 4 x menos 5 igual a 0

Answer 1

x²-4x-5=0
a=1 b=-4 c=-5

∆=b²-4ac
∆=(-4)²-4×1×(-5)
∆=16+20
∆=36


X=-b±√∆/2a
x=-(-4)±√36/2×1
x=4±6/2

x¹°=4+6/2. x²°=4-6/2=-2/2=-1
x¹°=10/2
x¹°=5

s={5,-1}