Question

A. A plumber charges $65 for a diagnostic check. After the check, it is $85 per hour for the work. Write an equation to model this sitaution.

B. Using the equation, how many hourscan you afford if you have $320?

Answer 1

A. 65 + 85x = total cost

B. He can afford 3.035 hours, or 3 if he has to pay for complete hours.

Explanation:

A. Let's set up our equation. The flat rate is 65, so

65 +

The continuous rate is 85/hr, so with x representing hours

65 + 85x

All this added together will equal the total cost, so

65 + 85x = total cost

B. Let's plug in $320 for our total cost.

65 + 85x = total cost

65 + 85x = 320

Simplify and solve for x. First subtract 65 from both sides.

85x = 320 - 65

85x = 258

x = 258/85 = 3.035 hours

Answer 2

Answer: To answer question A) we could write an equation in slope intercept form. The equation would be y = 85x + 65 with 85 being the work per hour (x) and 65 being the one time fee at the start for the diagnostic check. As for part B) we could simply insert 320 for y as that is the maximum amount of money we can afford. Doing this we would get 320 = 85x + 65 Now to solve we would isolate x by doing the following

320 - 65 = 85x

255 = 85x

255/85 = x

3 = x

x = 3

So the answer for part B would be that we could only afford 3 hours of work. I hope this has been able to help you!