You need to add a single line and make the statement true
All the numbers are made by matchsticks.
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Trivial Answer. If they are made by matchsticks, then:
Add a single matchstick obliquely on equal sign to make it non-equality sign. After all 5 + 5 is not equal to 5
An alternative solution:
Excuse the fact that there's a rotation issue - the markup for equations doesn't appear to permit rotations to fix it.