Question 557713
You can plot the two points and extend a straight line through them.
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You will find that the graph is a horizontal line (parallel to the x-axis) and 9 units above the x-axis at all points on the line. The graph crosses the y-axis at the value +9.
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The equation for this line is y = +9 and its graph looks like the horizontal red line through +9 on the y-axis in the figure below:
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{{{graph (300,300,-40,40,-2, 12, 9)}}}
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Hope this helps you to understand this problem.
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