Question

resolva as equações

a) 12+3x=36
b)36+12=3x
c)7x=49
d)x+10=18
e)2x-7=15
f)3x+2=-1
g)6x+12=54
h)4x+28=-24
i)9x-13=95
j)5x+17=82
k)3(x+4)+8=2+x
l)7(x-14)+20=5(x+3)-15
m)3x+12=36(x+1)

Answer 1

a) x = 8

12 + 3x = 36
3x = 36 - 12
3x = 24
x = 24/3
x = 8

b) x = 16

36 + 12 = 3x
48 = 3x
x = 48/3
x = 16

c) x = 7

7x = 49
x = 49/7
x = 7

d) x = 8

x + 10 = 18
x = 18 - 10
x = 8

e) x = 11

2x - 7 = 15
2x = 15 + 7
2x = 22
x = 22/2
x = 11

f) x = -1

3x + 2 = -1
3x = -1 - 2
3x = -3
x = -3/3
x = -1

g) x = 7

6x + 12 = 54
6x = 54 - 12
6x = 42
x = 42/6
x = 7

h) x = -13

4x + 28 = -24
4x = -24 - 28
4x = -52
x = -52/4
x = -13

i) x = 12

9x - 13 = 95
9x = 95 + 13
9x = 108
x = 108/9
x = 12

j) x = 13

5x + 17 = 82
5x = 82 - 17
5x = 65
x = 65/5
x = 13

k) x = -9

3(x + 4) + 8 = 2 + x
3x + 12 + 8 = 2 + x
2x = -18
x = -18/2
x = -9

l) x = 39

7(x - 14) + 20 = 5(x + 3) - 15
7x - 98 + 20 = 5x + 15 - 15
7x - 78 = 5x
7x - 5x = 78
2x = 78
x = 78/2
x = 39

m) x = -8/11

3x + 12 = 36(x + 1)
3x + 12 = 36x + 36
12 - 36 = 36x - 3x
-24 = 33x
x = -24/33
x = -8/11