The expression is 

       (Substitute)

To simplify the expression follow the order of operations: (PEMDAS)

1.      Evaluate the expressions inside Brackets/Parenthesis (P).

2.      Evaluate Powers/Exponents (E).

3.      Multiply and/or Divide in order from left to right (MD).

4.      Add and/or Subtract in order from left to right (AS).

A simple technique for remembering the order pf operations is turned into phrase

“Please Excuse My Dear Aunty Sally”

First operation is Evaluate the expression within the parentheses.

=          (Evaluate power: )

Next operation is subtraction.

=                 (Subtract: )

Next operation is multiplication.

=                     (Multiply: )

Next operation is division.

=                       (Divide: )

The value of the expression .