Note: I am assuming you meant to write the value of y = 12 instead of w = 12.
So, I am assuming y = 12
Answer:
The value of 13 - 0.75y + 8x when we substitute y = 12 and x = 1/2 will be: 8
Explanation:
Given the expression

Given
substituting y = 12 and x = 1/2 in the expresion




Therefore, the value of 13 - 0.75y + 8x when we substitute y = 12 and x = 1/2 will be: 8