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Teachers & SchoolsThis video explains how to use slope-intercept form to graph a line or find an x value when you know the y value and the slope. Just remember rise over run. To some people, y=mx+b is just a formula, but not to you after watching this video.

Algebra | Real Numbers and Quantities |

Language | English Language |

You better figure this problem out fast, or you'll be up the river Styx without a paddle.

Praise Olympus. We're here to help.

Does the equation look familiar? It's written in slope-intercept form.

m is the slope of the line...

and b is the y-intercept...

Great, but what does that mean? Since we are given a point of the line, and

the slope...

... we can find an infinite number of other points on the line and connect them.

Remember that slope (m) is equal to the change in y divided by the change in x.

Slope = "rise over run." The slope-intercept form of a line is written

out as y equals mx + b How do we graph this to Zeus' specifications?

Let's examine how to graph one of these equations: y = 3x + 4.

We know that the number in front of x is the slope, three, and that 4 is the y-intercept.

Well get this done before Cerberus intercepts you for dinner.

Start by plotting the y-intercept, which is four.

You'll put a dot at four on the y-axis, which is the vertical one.

Next, since we know that the slope is three, also known as three over one...

...we know that another point will be three up and one over... in the positive direction

of course...

Here's how you would graph this point on your scroll.

Finally, connect these points. It's like connect-the-dots, torture edition.

There you have it.

If you think this problem was torture, just be glad you're not pushing a boulder up that

slope for all eternity.