2x + 7 = 15
- 7 -7
-----------
2x = 8
=
x = 4
- 5 = -1
3· - 3·(5) = 3·(-1)
x - 15 = -3
+15 +15
------------
x = 12
30 = 16 + x
5·(30) = 5·(16) + 5·x
150 = 80 + x
-80 -80
------------
70 = x
7 + x = -1
3·(7) + 3·(2/3)x = 3·(-1)
21 + 2x = -3
-21 -21
--------------
2x = -24
=
x = -12
22 = 18 - x
4·(22) = 4·(18) - 4·x
88 = 72 - x
-72 -72
------------
16 = -x
16 = -1x
=
-16 = x
-7x + 4x = 9
-3x = 9
=
x = -3
3x - 7 + x = 5
4x - 7 = 5
+7 = +7
----------------
4x = 12
=
x = 3
12(2 - x) = 6
24 - 12x = 6
-24 -24
---------------
-12x = -18
=
x =
x =
(2x - 4) = 48
9·(2x - 4) = 9·(48)
-4(2x - 4) = 432
-8x + 16 = 432
-16 -16
----------------
-8x = 416
=
x = -52
+ 3 = 23
3· + 3·3 = 3·23
4x + 9 = 69
- 9 -9
-------------
4x = 60
=
x = 15
-10 = x + x
2·(-10) = 2·(x) + 2·x
-20 = 1·x + 2·x
-20 = 3x
=
= x
55x - 3(9x + 12) = -64
55x - 27x - 36 = -64
28x - 36 = -64
+ 36 = +36
---------------
28x = -28
=
x = -1
9x - 5(3x - 12) = 30
9x - 15x + 60 = 30
-6x + 60 = 30
-60 = -60
--------------
-6x = -30
=
x = 5
Edwin