Solving Equations
Learn how to isolate variables step-by-step and solve any basic equation with confidence.
+
•X =
X
What You’ll Learn:
-
Solve one-step equations -
Check your answers -
Avoid common mistakes -
Solve multi-step equations
Lesson 1:
One-Step Equations
Undo the operations to isolate the variables
- x + 5 = 12
- ⟶
- x = 12 – 5
- ⟶
- x = 7
Lesson 2:
Two-Step Equations
Variable on both sides
2x + 3 = 11
2x = 8
⟶
2x + 3 – 3 = 11 – 3
2x = 8
⟶
2x = 8
↙
x = 4
2x + 3 = 11
⟶
2x + 3 − 3 = 11 − 3
2x
2
=
8
2
⟶
2x = 8
x = 4
Check:
plug x = 4 back in:
1. 2x + 3 = 11
⟶
2(4) + 3 = 11
⟶
8 + 3 = 11 ✓
Lesson 3:
Variables on Both Sides
Isolate the variable by undoing operations in reverse.
5x + 2 = 3x + 8
⟶
2x + 2 = 8
⟶
2x = 6
⟶
x = 3 ✓
Practice Problems
Easy
- x + 4 = 10
Medium
- 2x + 5 = 15
Challenge
- 4x − 3 = 2x + 9
Common Mistakes to Avoid
-
Forgetting to do the same thing to both sides -
Distributing incorrectly -
Making arithmetic errors
Quick Recap:
To solve equations: isolate the variable
by undoing the operations in reverse order.
±
—
+
÷
—
=
ISOLATE
=
O
-
Undo addition or subtraction to isolate the variable. -
Undo multiplication or division. -
Check your solution.
Answer Key:
Easy:
x = 6
Medium:
x = 5
Challenge:
x = 6
Next:
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