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The Equation of a Straight Line

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This sample is an excerpt from one presentation on The Equation of a Straight Line in Boardworks Middle School Math, which contains 179 interactive presentations in total.

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Information

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Find the slope of a straight line

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Exploring slopes

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The general equation of a straight line can be written as:

y = mx + b

The value of m tells us the slope of the line.

The value of b tells us where the line crosses the y-axis. This is called the y-intercept, and it has the coordinate (0, b).

For example, the line y = 3x + 4 has a slope of 3 and crosses the y-axis at the point (0, 4).

The equation of a straight line

What is the equation of a line that passes through the origin?

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Investigating straight lines

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