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Write the equation of the line that is parallel to y = 9x+ 4 and crosses the y-axis at -3.

User Harshalb
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Answer:

y = 9x -3

Explanation:

The given line is in "slope-intercept form"

y = mx + b

where m is the slope and b is the y-intercept (where it crosses the y-axis).

In your given line, we have ...

m = 9, b = 4

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A parallel line will have the same slope, so we know that the line you want has m = 9. You are told to make the line cross the y-axis at -3, so that makes b = -3. Putting these values into the slope-intercept form gives the desired equation:

y = 9x -3

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The attached graph is intended to show the lines are parallel and the equation given here meets the requirement for a crossing of the y-axis at -3. The vertical and horizontal scales are different in order to better show these things.

Write the equation of the line that is parallel to y = 9x+ 4 and crosses the y-axis-example-1
User Lamonte
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3.5k points