One and Two Step One and Two Step EquationsEquations
Using Opposite OperationsUsing Opposite Operations
When working to get the variable isolated and all alone, use the opposites rule.
Opposites Rule – to get rid of a term from either side of an equation, just do the opposite operation.
1. C + 3 = 5
Variab
le
Mark the variable then leave it alone. Move everythingaway from the variable.
- 3 - 3
C = 2
2. m - 3 = 5+3
= 8
+3
m
Variab
le
3. P + (-12) = -5
“fix” double signs first
P – 12 = -5+12 +12
P = 7
4. Y - (-6) = 3 Y + 6 = 3
- 6 -6
Y = -3
“fix” double signs first
7. 9x = 45This reads 9 times xSo use the opposite.
Divide both sides by 9.9 9
x = 5
8. - 4m = - 28
- 4 - 4
m = 7
68
k
This is a division
Problem, use
Multiplication
to solve it.
9.
- k
(8) (8)
= 48 Now Divide By -1 - 1 - 1
k = - 48
10. 115
x
(-5) (-5)
= x 55
Let’s try a problem.Let’s try a problem.
8x + 5 = 618x + 5 = 61This problem has addition, so we need to subtract first.
- 5 - 5 Whatever we do on one side, we have to do on the other.
8x 56=
Now, Step 2.Now, Step 2.
8x = 568x = 56This problem has multiplication, so we need to divide now.
Whatever we do on one side, we have to do on the other.8 8
x = 7
Let’s try another problem.Let’s try another problem.
3a - 8 = 43a - 8 = 4This problem has subtraction, so we need to add first.
+ 8 + 8 Whatever we do on one side, we have to do on the other.
3a 12=
Now, Step 2.Now, Step 2.
3a = 123a = 12This problem has multiplication, so we need to divide now.
Whatever we do on one side, we have to do on the other.3 3
a = 4
Let’s try another problem.Let’s try another problem.
zz + 2 = 26 + 2 = 26 66This problem has addition, so we need to subtract first. - 2 - 2
Whatever we do on one side, we have to do on the other.
24=z6
Now, Step 2.Now, Step 2.
This problem has division, so we need to multiply now.
Whatever we do on one side, we have to do on the other.
z = 144
z = 246
6 • • 6
Let’s try one more problem.Let’s try one more problem.
mm - 10 = 15 - 10 = 15 55This problem has subtraction, so we need to add first. +10 +10
Whatever we do on one side, we have to do on the other.
25=m5