Answer:
f(4) = 5
Step-by-step explanation:
The notation used for a point is (x,y). The first number is the x and the second number is the y.
In function notation, you have f(x) = y.
The input number, x, is in the parenthesis beside the f. The output, y is all by itself on the other side of the equal sign.
For the point (4,5), 4 is the x so it goes by the f. 5 is the y so it goes by itself on the other side of the equal sign.
f(4) = 5