Question

Resolva as equações
a) 8x+9=3x+7
b) 2a-6=7a+15
c) 7y-12-4y=15-9y
d) 7x-5x+18=-2x+4

Answer 1

a) 8x + 9 = 3x + 7
8x - 3x = 7 - 9
5x = -2
x = -2/5

b) 2a - 6 = 7a + 15
2a - 7a = 15 + 6
-5a = 21
A = -21/5

c) 7y - 12 - 4y = 15 - 9y
7y + 4y + 9y = 15 + 12
20y = 27
y = 27/20

d) 7x - 5x + 18 = -2x + 4
12x + 2x = -18 - 4
14x = - 22
x = -22/14 = -11/7