Question

The graph below shows the cost of college tuition per credit hour at a local community college.

(graph in image)

Write the equation in slope-intercept form for the cost of college tuition in terms of the number of credits. Then, complete the table of values for the function.

y = __x + __


How much money, y, will it cost to take 12 college credits, x?

It will cost $___.

Answer 1

y = 350x + 225

It will cost $4425 for 12 credits

Explanation:

From the two points shown in the graph, we can write the equation of the line.

(5, 1975), (8, 3025)

slope = m = (y_2 - y_1)/(x_2 - x_1) = (3025 - 1975)/(8 - 5) = 1050/3 = 350

y = mx + b

y = 350x + b

1975 = 350 × 5 + b

b = 225

The equation is

y = 350x + 225

For 12 credits, x = 12.

y = 350 × 12 + 225

y = 4425

Answer: It will cost $4425 for 12 credits