Question

The fuction f (x)= -75x + 1,2000 represents the value of the your cell phone x months after you purchase

Answer 1

it for $1,200. The -75x term represents the depreciation of the phone each month, and the constant value of $1,200 represents the original purchase price.
For example, if you purchased the phone 5 months ago, you can calculate the current value by plugging in x=5 into the function:
f(5) = -75(5) + 1,200
f(5) = -375 + 1,200
f(5) = $825

So, after 5 months, the value of your cell phone would be $825.