Respuesta :

Due to pemdas you would have to start with multiplication. 3×12= 36. Then you do addition which would be 9+36= 45.
Just replace all variables that r with the variable r equivalent.

So, the expression 9 + r * 3 becomes 9 + 12 * 3

Use the order of operations to solve.

9 + 12 * 3
9 + 36 <--- The order of operations says that multiplication and division
                   have a higher precedence than addition and subtraction.
45 <--- Simply add.

So, the answer is 45.
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