Pearson Algebra 1 Common Core, 2011
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Pearson Algebra 1 Common Core, 2011 View details
2. Direct Variation
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Exercise 24 Page 304

The first point to graph in a direct variation equation is (0,0). How can you find another point using the slope?

Practice makes perfect
A direct variation equation follows a certain format. y= mx In this form, m represents the slope or constant of variation. If we highlight the coefficient of x in our given equation, we can see that the constant of variation is - 12.

y= -1/2 * x By rewriting - 12 as - 12, we can think of this as the ratio of rise over run. m=rise/run=- 1/2

This slope means that the graph decreases by 1 vertically as it increases by 2 horizontally. The graphs of direct variation equations pass through the origin, (0,0). To graph this equation, we will first plot a point at the origin and use the slope to plot a second point.

Finally, we complete the graph by sketching a line that passes through both points.