Question

resolver as seguintes equacoes do 1 grau
a) 18x-25=65
b) 3(x+5)-(x+7)=4(1-x)
c) 9x=21-5x
d) 23x-16=14-17x

Answer 1

a) 18x-25=65 
    18x=65+25
    18x= 90
     x= $\frac{90}{18}$
     x=5

b) 3(x+5)-(x+7)=4(1-x)
    3x+15-x-7=4-4x
    3x+4x-x=-15+7+4
     6x= 4
     x= $\frac{4}{6}$
     x=0.66

c) 9x=21-5x
    9x+5x=21
    14x=21
     x= $\frac{21}{14}$
     x=1.5

d) 23x-16=14-17x
    23x+17x=+16+14
    40x=30
     x=$\frac{30}{40}$
      x=0.75