Question

Resolva as equações completas do 2°grau
A) x²+4x+3=0
B) x²-x-20=0
C) 7x²+x+1=0
D) x²-7x+10=0
E) 2x²-10x-12=0
F) x²-8x+15=0
G) x²+3x-10=0

Answer 1

A) x²+4x+3=0
Δ=16-12
Δ=4
-4+2/1=-2
-4-2/2=-3

B) x²-x-20=0
Δ=1+80
Δ=81
+1+9/2=5
+1-9/2=-4

C) 7x²+x+1=0
Δ=1-28
Δ=-27 (não tem raíz!)

D) x²-7x+10=0
Δ=49-40
Δ=9
+7+3/2=5
+7-3/2=2

E) 2x²-10x-12=0
Δ=100+96
Δ=196
+10+13/4=23/4
+10-13/4=-3/4

F) x²-8x+15=0
Δ=64-60
Δ=4
+8+2/2=5
+8-2/2=3

G) x²+3x-10=0
Δ=9+40
Δ=49
-3+7/2=2
-3-7/2=5

Espero ter ajudado!