Question

Calcule o valor das incógnitas
1) 2x+90=x+120
2) 4y-120=y-30
3) 9x+50-6x=70

Answer 1

a)2x-x=-90+120
x=30

b)4y-y=+120-30
3y=90
y=90/3
y=30

c)9x-6x=-50+70
3x=20
x=20/3
x=6,666...

Answer 2

fica assim::
2x+90=x+120
2x-x=120-90
x=30

4y-120=y-30
4y-y=-30+120
3y=90
y=90/3
x=30

9x+50-6x=70
3x=70-50
3x=20
x=20/3
x=6,6
espero ter ajudado!