4.
3 ( 4 - 2 x ) = - 2 x
3 * 4 - 3 * 2 x = - 2 x
12 - 6 x = - 2 x Add 6 x to both sides
12 - 6 x + 6 x = - 2 x + 6 x
12 = 4 x Divide both sides by 4
3 = x
x = 3
Answer d
5.
5.4 + 0.2 x = - 1.4 x + 8.6 Subtract 5.4 to both sides
5.4 - 5.4 + 0.2 x = - 1.4 x + 8.6 - 5.4
0.2 x = - 1.4 x + 3.2 Subtract 3.2 to both sides
0.2 x - 3.2 = - 1.4 x + 3.2 - 3.2
0.2 x - 3.2 = - 1.4 x Subtract 0.2 x to both sides
0.2 x - 0.2 x - 3.2 = - 1.4 x - 0.2 x
- 3.2 = - 1.6 x Divide both sides by - 1.6
- 3.2 / - 1.6 = x
2 = x
x = 2
Answer a
6.
- 4 - 5 ( x + 8 ) =
- 4 - 5 * x - 5 * 8 =
- 4 - 5 x - 40 =
- 5 x - 44
Answer a
7.
3 x + 4 ( x - 6 ) - 3 ( x - 7 ) =
3 x + 4 * x + 4 * ( - 6 ) - 3 * x - 3 * ( - 7 ) =
3 x + 4 x - 24 - 3 x + 21 =
4 x - 3
Answer b