Answer:
 a) (0, 50); 0 hours cost $50; not impossible
 b) (-2/3, 0); -2/3 hours cost $0; impossible
Step-by-step explanation:
a)
The ordered pair (h, c) tells you the cost (c) of renting a backhoe for h hours. The ordered pair (0, 50) is the vertical intercept. It tells you the cost of renting the backhoe for 0 hours is 50 dollars.
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b)
The horizontal intercept is the value ordered pair where c=0. It can be found by solving the equation for c=0:
 c = 75h +50
 0 = 75h +50
 -50 = 75h . . . . . . subtract 50
 -2/3 = h . . . . . . . . divide by 75
The horizontal intercept is (-2/3, 0). It tells you the cost of renting the backhoe for -2/3 hours is 0 dollars (free). We generally consider this to be impossible.
