Claire's monthly due is $15, so her slope is a slope of -15x since it's being taken away. Knowing this, you can figure out how much money she had in the beginning by adding $30 to the $450. Her equation is -15x+480. Now plug in an x for both of them. preferably by 10s. in about 30 months, Marshall will only have 10 dollars and Claire will have 30. Claire is still gonna have 2 more months than Marshall.
