Smart Math guide · Algebra Smarts

Treat an Equation Like a Balance

Whatever operation you perform on one side of an equation must preserve equality on the other side.

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The method

How to use it

  1. Simplify each side where helpful.
  2. Undo operations in reverse order.
  3. Check by substitution.
Worked example

See it in action

3x+5=20 → 3x=15 → x=5.

Check your thinking

How to verify it

3(5)+5=20.

Keep learning

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