Two-step equations
Solve 8x + 13 = 45
The aim is to get x on its own. Whatever we do to one side, we do to the other, so the equation stays balanced. This one takes 2 steps.
- 8x + 13 = 45The question.
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Step 1: Subtract 13 on both sides −13
On the left, the x part has + 13 with it. Take 13 away from both sides to get rid of it.
8x = 32On the left, the 13 cancels out.
+ 13 is undone by − 13.
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Step 2: Divide by 8 on both sides ÷8
8x means 8 × x. Divide both sides by 8 to get x on its own.
x = 4x is on its own. x = 4.
Multiplying is undone by dividing.
Answer: x = 4
Check it
Put x = 4 back into the question. If both sides come to the same number, the answer is right.
Left side: 8x + 13 → 32 + 13 = 45
Right side: 45 → 45
✓ Both sides are 45, so x = 4 is right.
Now try it yourself
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