WEBVTT

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Here is the problem: 5 equals 2y minus 1.

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A linear equation in y: isolate y using inverse operations.

3
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Start with the equation.

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Subtract 2y from both sides.

5
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Subtract 5 from both sides.

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Divide both sides by negative 2.

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So the answer is y equals 3.

8
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Doing the same operation to both sides keeps the equation balanced. Undoing addition, then multiplication, leaves y alone.

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y equals 3: left side equals 5, right side equals 5, which checks out.