Resposta :
Resposta:
x²+10x+21=0
∆ = b²-4ac
∆ = 10²-4.1.21
∆ = 100-84
∆ = 16
x = -b±√∆/2a
x = -10-4/2.1
x = -14/2
x = -7
x = -10+4/2.1
x = -6/2
x = -3
S = {-7 , -3}
Resposta:
x²+10x+21=0
∆ = b²-4ac
∆ = 10²-4.1.21
∆ = 100-84
∆ = 16
x = -b±√∆/2a
x = -10-4/2.1
x = -14/2
x = -7
x = -10+4/2.1
x = -6/2
x = -3
S = {-7 , -3}