How do you simplify #8+7(4^2-3)#?
In an expression which has a variety of operations, count the number of terms first.
Each term must simplify to a single number and these answers are added or subtracted in the LAST step.
In each term do the strongest operations first, - the powers and roots. Then any multiplication and division.
Brackets (parentheses) indicate when a weaker operation has to be done before a stronger one.
In the calculation, red shows what has been done in each step.