Question

resolva as equaçoes do 2 grau
d)x ao quradrado-5x+8=0

Answer 1

x²-5x+8=0

a=1
b=-5
c=8

▲=b²-4.a.c
▲= (-5)²-4.1.8
▲=25-24
▲=1

x=-b (+ ou -) V▲/ 2.a
x= 5(+ou-)1/2
x'=5+1/2
x'=6/2 = 3
x''=5-1/2
x''=4/2 = 2

S:{ 3,2 }