MathBench > Measurement

Straight Lines/ Standard Curves

A Line has only 1 Slope

A line is very simple in that it has the same slope everywhere. So, to find out how much a PC tech makes per hour, you just need to measure how much we made in any single hour such as the first one:


If you want to get fancy, you can pick a different hour, but to me it seems like more work for the same answer. For example, you could say, between hours 1 and 2, the PC Tech earned $42 - $21 = $21 extra dollars:


I mention this only because when people want to demonstrate finding a slope, they often draw a figure that looks like this;


But you now know that, assuming that the line goes through (0,0) , its much easier to find the slope by just finding the value of y at x=1. If it's not possible to distinguish the value of y at x=1, then you may need to use a larger number:

What is the pay rate for the forest conservation worker? How about the veterinarian?


(All wage data taken from

(To make this problem interactive, turn on javascript!)

I think I have the answer:
Forester = $22/hr,
Veterinarian = $42/hr

The equation for a straight line is


"Y-intercept" is just a fancy word for "where the line crosses the y axis". We know that the lines we're talking about go through (0,0) -- there, the y-intercept must be zero, so the equation is simply y = mx.