x
When a one step equation is solved, essentially the constants are sorted to
one side of the equation and the variable to the other. x
3 x
20
8
8
5 x
3 x 3x
2x
Think of this as “moving” the constant 8 to the other side of the equation.
“Move” terms involving variables the same way.
2 Choose the term containing the variable with the smaller coefficient.
This doesn’t matter now, but will make things easier in other
2 equations.
2 2 Now there is only a two step equation to solve.
10
2x
10
2
2 x
2
5
x
To solve equations with variables on both sides of the equal sign, first distribute. 2 ( 3 x
8 )
5
7 x
Then combine like terms.
Move all the variables to the same side.
6
13 x x
16
21
5
9
x
7
x
6
8
9 x
Solve the two step equation.
9 x
4 x
21
6
Subtract or add, and then divide.
21
21
Every step isn’t needed in every equation. 4 x
27
8
( 2
2
x x )
8 x
8 x x
27
4
6 3
4
Practice: a) 5x - 8 = 7x + 3 b) 3d - 1 = 4d + 9 c) 7x + 4 = 5x - 8 d) 6 - 5c = 2 + 9c e)
2 x
3
7
4 x
8
2 x
7 f) 0.23x-7x+4=4x-0.6+4x-8 g) 4
2 x
8
2
3 x
2s - 8 = 3s + 9
3s - 9 = 2s +10
4s - 10 = s + 11
-11 + s = 4s + 12
4 2
3
x
1 7
8
7 x
9
12x-(5-3x)=7-9(2-3x)
3 2
3 x
7
2 5
8 x
3 1
2
3
4 x
8
3
4
8 x
50X - 80 = 70X + 30
4L - 12 = 8 +5L
2K + 3 = 6K - 4
4x - 10 = 10x + 4
3
s
5
12
16
7
s
4
15
3 x
2 x
4
3 ( 2 x
8 )
4 x
5 x
8 ( 2 x
1 )
h) 5 t
3
2
7 t
12
3 t
2
t
i) 15
8
3 x
4 x
8
3
x
j)
x 5
9 x x k) l) m)
3 x ( x x
23 x ( x ) x
3 x x 4 x 2
123
8
2 x
5
15 ( 3 x
5 )
23
5 x
2
5
x
3
4
x
3 1
3
7
8
3 x 2 x 7
8 n) o) p) q) r) s) t)
5
3 x
2
34 x
7
24 x
8
4
2 x
17 x
4
3 x
5
10 x x 10
x 2
x x x x x x x
d
7
d
4 d
d
4 d
8 t
t
7
5 t 9 21
2 t
7
10 t
x
8
3 x
9
x
13 x
4 x
5 x
8
z 8
z 9
z
3 b
b
9
3 b
10
5
9 8 x
x 5
2
7 x
5
9
n
4
5
3 n
n
n
8
3 x
8
2(4 x
5)
(2
x
2(3 - (4 y + 8)) - (9 -2(3 y + 5)) = (2 y - 8) - 8 - (5y ) - 9 y + 10
f
f
8
f
9
5
f
5
f
7
f
8
12
15
The proportions on this page require the algebra methods learned to solve.
Example:
2
9 x
8(2
16
7 x x
7 x x
5
x
8
5) 7(
40 7
40 14 x
7
2 x x
2)
14
Cross multiply.
Then distribute.
Subtract to get the variables to the same side of the equation.
Solve the two step equation.
40 40
9 x 54 x 6
Practice: a)
2 a
3
9
3 a
5
8 2 x
3
5
3 x
5
8 m b)
2
3 a a
9
2
8
5 m m
10
4
5 2 3
10
7
2 9
5 f f
10
15 m
5
4 c)
9 8 s 9
1 5 s 10
3
4
t t
3
8
24
8
10 k k
8 d)
6
8
5 y
8
10 3
16
w
w
8
5 u
45
8
5 u
3
10
Remember to solve proportion problems, cross multiply, and then solve.
Examples: x
8
7
3
4
2
5 x
5 x
100
1
4
x
7
24 100
2 x
5
5 x
1
4 x
28
24 200 x
25 x
5
28
28
4 x
52
175 x
5 x
1
35 x
4 x
4
13
52
4
Practice: a) x
4
5
b) x
6
2
3
8 c)
2 x
9
4 1
3 d)
3 x
5
5 x
6
2
3 x
5
5
8
2 x
3 x
5
8
( x x
7
3 3 8
)
3
2
( x x
)
3
3 x
x
3
x
5
2
2
4
3
x
5
9 x
6
4 x
20
4 x
4 x
5 x
6
6
20
6
5 x
26 x
5 1
5
2 x
8
7
5
3 x
2 x
6
7
3 x
5
8 x
2
6
3 x 5
5
6
3 x
x
2