Question 88912: How do I do this?
List and verify two intercept points (ordered pairs) that are solutions for the equation 5x – 4y = 20?
Thank you so much
Answer by bucky(2189)   (Show Source):
You can put this solution on YOUR website! I presume that by "intercept points" your problem is asking you to find the ordered
pairs where the graph crosses the x-axis and the y-axis.
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Think about the y-axis. Any point on the y-axis will have zero for it's x-value. For example,
(0, 10), (0,0), (0,-5) are all points on the y-axis because they have zero as their x
value. So in this problem, the way to find the y-axis intercept is to set x equal to zero
and then solve for the corresponding value of y.
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Let's do it ...
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5x - 4y = 20 <=== set x = 0
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5(0) - 4y = 20 <=== multiply 5 times 0 and the term 5(0) disappears
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-4y = 20 <=== divide both sides by -4 to solve for y
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y = 20/(-4) = -5
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So the y intercept for this problem is (0, -5). The graph crosses the the y-axis at a value
of -5.
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Now let's find where the graph crosses the x-axis. Any value on the x-axis has a y value
of zero. For example, (-6,0), (0,0), and (8,0) are all points on the x-axis. All you need
to do is to set y equal to 0 in the equation of this problem to find the corresponding
value of x where the graph crosses the x-axis.
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5x - 4y = 20 <=== set y = 0
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5x - 4(0) = 20 <=== multiplying 4 times zero results in 0 so that term disappears
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5x = 20 <=== solve for x by dividing both sides by 5
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x = 20/5 = 4
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Therefore, the point (4, 0) is the intercept point on the x-axis.
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In summary, two intercept points are (0, -5) on the y-axis and (4, 0) on the x-axis.
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The graph of this equation might help you to understand the problem, so here it is:
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Hope this helps you to understand the problem.
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