WEBVTT
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Which of the following functions has a greater π¦-intercept?
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For function a, we can look on the graph.
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The π¦-intercept is the place that crosses the π¦-axis.
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And this function crosses the π¦-axis at two.
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For function b, itβs not as immediately apparent what the π¦-intercept is.
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There are a few options.
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First, we recognize that the π¦-intercept is always found at the point π₯ is zero.
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When π₯ equals zero, we have our π¦-intercept.
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We can also notice the rate of change for this function.
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As π₯ moves up one, we add four to the π¦-values.
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The rate of change is then four over one.
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We also call this the slope.
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And that means that to go from negative one to zero is an increase of one on the π₯-axis and would need an increase of four on the π¦-axis.
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Negative three plus four equals one.
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Function b has an intercept at the point zero, one.
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If we wanted to confirm this, we could plot the other points on the graph.
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Taking a second look at the graph confirms that function a has the greater π¦-intercept.