WEBVTT
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Write the function that is represented by the graph.
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If we think about the π¦-intercept form, π¦ equals ππ₯ plus π, we need the slope of the line and the π¦-intercept to write its function.
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The π¦-intercept is the place where the line crosses the π¦-axis.
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Notice here that the π¦-axis is being called π of π₯, the function of π₯.
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We can also say π of π₯ equals ππ₯ plus π.
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But back to the π¦-intercept.
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The place where it crosses the π¦-axis on this graph is three.
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π of π₯ equals the slope times π₯ plus three.
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To find the slope, letβs consider the changes in π¦ over the changes in π₯.
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Hereβs an example.
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As we go down two from three, so down two on the π¦-axis, we go over three on the π₯-axis.
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Down two, right three gives us a slope of negative two-thirds.
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And weβve already considered that the π¦-intercept is three.
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The function represented by this graph is π of π₯ equals negative two-thirds π₯ plus three.