Answer:
Speedy Taxis
Explanation:
I solved this by using a graphing calculator. Speedy Taxis shows the least cost for x=30.
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You can figure the cost of each for x=30
1.5(30) = 45
1.1(30)+11.5 = 33+11.5 = 44.5 . . . . . lowest cost
1.25(30)+8 = 37.5+8 = 45.5
Speedy Taxis is the cheapest for a trip of 30 miles.