Question

Andre is paid $4 per hour for the first 30 hours he works every week. He makes $5 per hour for each hour he works over 30 hours per week. In other words, total wages = fixed wages for 30 hours + additional wages at $5 per hour. Write a function that gives Andrew's total wages when he works more than 30 hours.

Answer 1

Since we are not concerned about when hours are less than 31.

For the first 30 hours he earns 4*30=$120.  So as a linear equation 120 is the y-intercept and since he earns $5 per hour after 30 hours the slope, or rate of change is 5 thus:

y=5(x-30)+120 where y is wages in dollars and x is total hours worked

y=5x-150+120

y=5x-30