Answer:
f(-3) = 15
Step-by-step explanation:
Given that,
f(x) = -x + 12
You have to solve for,
f(-3) = ?
For that,
you have to put (-3) instead of x
f (-3) = -x + 12
= -(-3) + 12
= +3 + 12
= 15
Hope this helps you.
Let me know if you have any other questions :-)