In order to become a member at a local gym, there is a $50 startup fee, then a $20 fee every month. Write an equation in slope-intercept form modeling this situation where *c*, the total cost, is a function of *g*, the number of months spent at the gym.

*c* = *g* +

No matter how many months you spend at the gym, if you want to become a member, it will cost $50. This can be thought of as the *y*-intercept, or *b* value.

After this, the total cost increases by $20 each month, so this can be thought of as the slope.

The equation for this situation is therefore *c* = 20*g* + 50.