Solving Two-Step Equations

The key to solving two-step equations is to always move the number added/subtracted to the variable first. (If you move the number multiplied/divided first, you have to distribute the number to each term, which adds extra work.)

Here's how it's done:

1) 2y + 5 = 3 We must move the number added first, which is the 5. To
do this, remember that we add the opposite to both sides.
2y = -2Now we'll simplify what we can and bring everything else down.
Now we are back to a one-step equation in which the 2 is being multiplied. We'll move it by dividing both sides by 2.
y = -1We have the variable all by itself, so this is our answer. Check our answer:
-2 + 5 = 3 True

2) -14 = -3x - 8 If having the variable on the right is confusing to you,
-3x - 8 = -14 switch the sides.
We must move the number added first, which is the -8
To do this, remember that we add the opposite to
-3x = -6 both sides.
Now we'll simplify what we can and bring everything else
down.
Now we are back to a one-step equation in which the -3 is
being multiplied. We'll move it by dividing both sides
x = 2 by -3
We have the variable all by itself, so this is our answer.
Check our answer:
-14 = -6 - 8 True


Practice: Solve each equation and check your answer.

1) 4x + 2 = 14

2) -2y + 8 = 2

3)

4) 3 = 2x - 8

5)



Answers:1) x = 32) y = 33) x = 124)5) y = 20

Related Links:
Math
Algebra
Factors


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