Question

resolução de equações 1)8a+2=6a+4 2)-21x-7=-x+53 3)2x-3+x=18

Answer 1

1)

8a + 2 = 6a + 4
8a - 6a = 4 - 2
2a = 2
2a = 2
----  ----
 2     2
a = 1

2)

-21x - 7 = -x + 53
-21x + x = 53 + 7
-20x = 60
-20x = 60
-------  -------
 -20      -20
 x= -3

3)

2x - 3 + x = 18
2x + x = 18 + 3
3x = 21
3x = 21
----  -----
 3     3
x = 7

Answer 2

1)8 a + 2 = 6 a + 4 
8 a - 6 a = 4 - 2
2 a = 2
a = 2/2
a = 1

2)-21 x - 7 = -x + 53 
-21 x + x = 53 + 7
-20 x = 60
x = 60/-20
x = -3

3)2 x - 3 + x = 18
3 x - 3 = 18
 3 x = 18 + 3
3 x = 21
x = 21/3
x = 7