The answer is 20 because you have to do the slope formula
The y intercept is when x = 0 so it is:-
8(0) + y = 8
0 + y = 8
y = 6 <------- y-interdept
x intercept is when y = 0 so:-
8x + 0 = 8
x = 1 <-------- x intercept
2.16 is greater. To do this start from the left and compare the numbers. For example, 2 is the same in both but 1 is greater than 0, so the answer is 2.16.