Respuesta :

First solve the inner parenthesis.

[7 * (5)] - 20

Solve what is in the parenthesis.

35 - 20= 15

Hope this helps!
randgh
  (7 x (5) )  -20 =

35-20 =15

the math rule  PEMDAS we should calcuculate in this order 
Parentheses, Exponents, Multiplication and Division, Addition and Subtraction!