With a Number Inside

The factors inside the parentheses do not have to be letters. (3y)^2 has two factors inside, 3 and y, and each one takes the power: 3^2 × y^2. Then work out the number's power: 9y^2.

Squaring 3y squares the 3 as well as the y. So (3y)^2 is 9y^2, never 3y^2. The example also shows why doubling the side of a square makes its area four times bigger: the new side 2s squared is 4s^2.

To raise a product to a power, apply the exponent to every factor inside the parentheses. Then work out any numerical powers, so 3^2 becomes 9.