ShmoopTube

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Here's your shmoop du jour, brought to you by Line Equations. Whose Line Equation is

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it anyway? What is the equation of this graph?

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And here are your potential answers...

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This graph shows us the two points of intersection; they are here at point 5 on the x-axis...

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and here at 2 on the y axis. So right off the bat, we know that 2 points

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on the line are .5, 0 and 0, 2. And since the line slopes downward, we know

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its slope will be negative.

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Now back to our old friend y equals mx plus

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b, the standard form of a line. We can get the slope m by doing the

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y over x dance like this...

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and we get y2 minus y1 over x2 minus x1...

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...or 2 minus 0 over 0 minus .5... ...which equals negative 2 divided by a half

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or... negative 4. So we have y equals negative 4 times x plus

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b...and we can just plug in some points to get b. Let's try the 2nd point - zero, 2

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We have 2 equals negative 4 times 0 plus b or... 2 equals... b.

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Which is answer C.

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