Question

The price of a cell phone can be modeled by the equation:

y = 15x + 90, where x is time in years and y is the price of
the phone. This equation tells us that the cell phone originally
cost $90 and each year the cost went up $15. How many years
will it take for the cell phone to cost $150?

Answer 1

4 years to cost $150

Explanation:

Just add +15 to each year until $150

Answer 2

4 years I’m pretty sure.