Answer
$55$
Work Step by Step
Recall the acronym PEDMAS, which tells us the order of operations:
P: Parenthesis and other grouping symbols
E: Exponents
D/M: Division and Multiplication (from left to right)
A/S: Addition and Subtraction (from left to right)
Use the rule above to obtain:
(Recall, $a-(-b)=a+b$.)
$=64-36 \div 9 \cdot 4 - (-7)
\\=64 - 4 \cdot 4 -(-7)
\\=64 - 16 -(-7)
\\=48-(-7)
\\=48+7 $
$\\=55$
