Square of a Number

Squaring a number means multiplying it by itself, so the result depends on both the size of the number and the fact that it is used twice. For example, 5² means 5 × 5, which equals 25. This idea comes up whenever you are finding the area of a square with side length n, because area = side × side.

Use this formula when a problem asks for a number multiplied by itself, or when calculating the area of a square. It also appears often in geometry, algebra, and science when a value is compared with itself twice.

• Thinking 6² means 6 × 2 instead of 6 × 6
• Adding the number to itself instead of multiplying it by itself
• Forgetting that a negative number squared becomes positive, for example (-4)² = 16