The rental company you have chosen charges a $70/day fee plus $0.20 for every mile you travel. Write a linear equation that expresses the total cost y, where x represents the number of miles you travel. Graph this equation. Then choose a number of miles, x, you travel that day and find the total cost of renting the truck.

This is a linear equation of the form y = mx + b, where m is the rate of change and b is the y-intercept, also known as the value of y when x = 0. Our independent variable is the number of miles we travel, and we will call that x. If we pay. 20 per mile, and miles is "x", we represent that as. 20x. The 70 is the amount we will pay per day even if we drive 0 miles. Therefore, the equation is:

y =.20x + 70.

I cannot graph this for you here.

We can choose a number of miles, say 100, and solve for our cost:

y =.20 (100) + 70

y = 20 + 70

y = 90

We can expect to pay $90 if we drive 100 miles in a day.