# What is a slope in mathematical terms

Alissa Fong. It's really important when you're looking at word problems that you keep in mind the units that go with your X and Y values so you can relate the slope back to the real world. What it means is we're just notating using what's called a subscript.

That's one thing you want to keep in mind. Alissa is currently a teacher in the San Francisco Bay Area and Brightstorm users love her clear, concise explanations of tough concepts. I would change like five inches per day or something like that. I just made that up. It doesn't mean take your Y value and multiply it by 2 or take your Y value and multiply it by 1.

## Slope formula

That's why we call it a ratio. That's my second Y value. Change in Y on top of change in X. You guys are going to do all kinds of practice with this. This means change in Y on top of change in X.

X from my second point I'm going to use that little 2 to show it's my second point. That's something that I help -- or helps me remember what slope means. The line is equally steep the entire time.

Decreases from left to right, it's called a negative. This triangle is the Greek letter delta, which is tricky.

That's why we call it a negative slope. A couple other things I want you to keep in mind with slope, and that is sometimes slopes are positive numbers and sometimes slopes are negative numbers.

That's a whole lot to keep in mind when you guys approach your problems. This is the same thing just written in a different way. So you'll get used to it.