Order of Operations Subtitles

-3²

-3² = -9

Exponentiation first (3 • 3 = 9), and then take the opposite of 9 to get -9.

(-5)²

(-5)² = 25

Because of the grouping symbols, take the opposite of 5 first, and then square it (-5 • -5) to get positive 25.

-6²

-6² = -36

Exponentiation first (6 • 6 = 36), and then take the opposite of 36 to get -36.

(-12)²

(-12)² = 144

Because of the grouping symbols take the opposite of 12 first, and then square it (-12 • -12) to get positive 144.

x² when x = -4

x² when x = -4 is equal to 16

When substituting a value for a variable, it's as if the value is wrapped in parenthesis.

(-4)² = 16

6 + 2 - 3

6 + 2 - 3

= 8 - 3

= 5

When an expression has a mixture of addition and subtraction, always work left to right.

If you want to work in any order, first convert the subtraction into addition of the opposite:

6 + 2 - 3

= 6 + 2 + (-3)

= 5

3x - 2 + 7

3x - 2 + 7

= 3x + 5

Did you get 3x - 9? If so, you forget to work left to right -- Start at 3x, subtract 2, and then add 7.

Another way to think about it is 3x + (-2) + 7. Start at 3x, add -2, and then add 7.

Working left to right when you have a mixture of addition and subtraction is very subtle and very important.