Respuesta :
This is a simple substitution task. Simply replace x with 5, thus the expression becomes:
7 (4+5).
Using the rules of calculation means solving the expessions in the brackets first thus you are left with 7(9) = 7*9
7 (4+5).
Using the rules of calculation means solving the expessions in the brackets first thus you are left with 7(9) = 7*9