Given :-
To Find :-
Solution :-
The given function is ,
→ f(x) = -9x + 7 .
And we need to find out its value at x = 3 , that is f(3) . So just substitute x = 3 ,
→ f(3) = -9*3 +7
→ f(3) = -27+7
→ f(3) = -20
Hence the required answer is-20 .
I hope this helps.