You need to use order of operations (PEMDAS)
= 23 + 12/4 Everything in Parentheses must be done first, using PEMDAS.
= 8 + 12/4 Exponents is done next.
= 8 + 3 Next is Multiplication and Division from left to right.
= 11 Finally, Addition and Subtraction from left to right.
PEMDAS is a mnemonic: Please Excuse My Dear Aunt Sally.