Question

calcule o valor X
a) 2x - 30 + 3x + 10=180
b)4x - 5 = 2x + 87
c) 2x + 30 + 50 =90
d)2x + 35 = 4x - 5

Answer 1

a) 2x - 30 +3x +10 = 180
    5x = 180 - 10 + 30
    5x = 170 + 30
    5x = 200
    x = 200/5 x = 40

b) 4x - 5= 2x + 87
   4x - 2x = 87+ 5
   2x = 92
   x = 92/2 

c) 2x + 30 +50 = 90
    2x = 90 - 80
   x = 10 /2 = 5

d) 2x + 35 = 4x - 5
    2x - 4x = -5 - 35
   -2x = -40 (.-1)
    2x = 40
    x = 40/2 = 20