Question

1- Considerando que x e er, resolva as equações
a) (4x+2.)²=36

b) (3x-9)²=36

pf respondam

Answer 1

a) (4x+2)^2=36
4x^2+2.4x.2+2^2=36
16x^2+16x+4=36
16x^2+16x+4-36
16x^2+16x-32=0
delta=b^2-4ac
delta=16^2-4.16.(-32)
delta=256+2048
delta=2304
x=-b-/+ raiz de delta/2a
x=-16-48/2.16
x=64/32
x=2
x=-16+48/2.16
x=32/32
x=1
b) (3x-9)^2=36
3x^2-2.3x.9+9^2=36
9x^2-54x+81=36
9x^2-54x+81-36
9x^2-54x+45=0
delta=b^2-4ac
delta=(-54)^2-4.9.45
delta=2916-1620
delta=1296
x=-b-/+ raiz de delta/2a
x=-(-54)-36/2.9
x=54-36/18
x=18/18
x=1
x=-(-54)+36/2.9
x=54+36/18
x=90/18
x=5