100=2.5h-15 in a word problem

Vanessa is trying to make 100 dollars to buy a bike. She already has 15 dollars, and she makes 2 dollars and 50 cents every time she walks her dogs for an hour. How many hours does she have to work in order to get 100 dollars?

That should do it.

Question from Equation

A

Suppose that h (in hours) represents the number of hours that an incandescent light bulb must be left on in order to heat a very small crawlspace underneath a house. Suppose further that the wattage of the bulb will be the only factor affecting the number of hours the bulb has to stay on. Let the wattage of the Bulb be B. There is a correction factor of C that can be subtracted from the term containing h.

Write a general formula for the what the equation says.

B = 2.5h - C

B

If the wattage of the bulb is 100 and and the Correction factor is 15, how many hours does the bulb have to stay on.

100 = 2.5h - 15

115 = 2.5h

2.5h = 115

h = 46 hours