# 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 Monster.com)

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

• I need a hint ... : It's not really possible to see (the value of the paycheck)at x = 1 hour. So pick a bigger x value, like x = 10 hrs.

• ...another hint ... : If the forester works 10 hours, she makes 220 dollars...

• ...another hint ... : 220 dollars / 10 hours = ? dollars / 1 hour

• ...another hint ... : Now do the same for the vet...

#### 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.