Question

Encontre os conjuntos soluções das equações completas.
a)x²-9x+14=0
b)x²+7x+10=0
c)3x²-7x+2=0
d)x²-20x+100=0
e)7x²-5+1=0

Answer 1

a) x²-9x+14=0
a=1;b=-9;c=24
∆=a²-4.ab
∆=(-9)² -4.1.14
∆=81-56
∆= 25
x=(-b)±√∆/a.2
x=-(-9)±√25/2.1
x=9±5/2
×'=9+5/2 =7
x"=9-5/2=1

b)x²+7x+10=0
∆=7²-4.1.10
∆=49-40
∆=9
x= -7±√9/2
x=-7± 3/2
x'= -7+3/2=-1
x"=-7-3/2=-5

c)3x²-7x+2=0
∆=(-7²)-4.3.2
∆=49-24
∆=25
x=-(-7)±√25/2.3
x=7±5/6
x'=7+5/6=2
x"=7-5/6=2/6=1/3