The coefficient is the number in front of the variable. If there isn't a number, it is understood to be a 1
For this problem you need to put the x values in for x in the equation. For example, put -10 in for x and calculate y, which is g(x)
Slope-Intercept form - y = 4
The differnce quotient is basically taking the derivitive (result will be f'(x)=5, but anyway)
here is the disffernce quotient

so
for your equation



h's cancel and you are left with 5
the differnce quotient is 5