ShmoopTube

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Here’s your shmoop du jour...

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What is the x-intercept of the equation 2x - 7y = 14?

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And here are the potential answers…

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So… what’s an intercept?

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An intercept – in algebra – is the part of the line that crosses the primary axis.

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That is, the x intercept is where the line crosses the x axis like… here… and the

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y axis is where it crosses… yes, shocker… the Y axis… here.

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So to solve the problem, we have to figure out what y is when x equals zero, and vice versa.

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We can just plug in zero for x in the equation, to get 2 times zero, which is zero…

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minus 7y equals 14.

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Divide both sides by negative 7 and we get y equals negative 2.

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Yeah, we didn’t HAVE to do that part to answer the question but it can’t hurt to

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know for future reference.

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Now we can plug in 0 for y to get 2x minus 7 times zero, which is 0, equals 14…

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…so 2x equals 14. Now divide both sides by 2 and x equals 7.

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The line crosses the x axis when x equals 7…

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…and so our answer is D. Done.

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