Well we know that our function is -3, so we can plug this into the equation. \
f(x) = 2x + 1 + 5
f(-3) = 2(-3) + 1 + 5, now from here we simplify (:
-6 + 1 + 5 then finally we combine our like terms
-6 + 1 equals -5, then -5 + 5 equals 0
our final answer is zero if our function is f(-3) ((((((((((((((((((((((((((((((: