Question 1109949
if it is f(x), when x=0 the constant is 4
The x term must be 15, and x=5 and there are 4 of them, so 4*5*some function of x must equal 15
x=15/20 or 3/4.
4(3/4)x=3x
when x=5, 3x=15
Therefore, (3/4)x+4=19
That is consistent with f(0)=4 and 4f(5)=15+4=19