Question 105887
Given that the equation of a line is 
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y = (1/3)x + 7
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To find if a point lies on this line substitute the x-value of the point for x in the equation
and substitute the y-value of the point into the equation. If both sides of the equation
are equal, then the point satisfies the equation and therefore lies on the line.
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Let's try the point (3, 8). In the given equation substitute 3 for x and 8 for y. When you
do the equation becomes:
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8 = (1/3)*3 + 7
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On the right side when you multiply 3 times (1/3) the result is 1. This makes the equation
become:
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8 = 1 + 7 or 8 = 8
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Since the equation is true for the point (3, 8), the point lies on the line.
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Let's try the second point (0, 7). In the equation let x = 0 and y = 7. Substituting 
these values into the equation results in:
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7 = (1/3)*0 + 7
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The multiplication of (1/3) times zero results in zero ... So the equation becomes:
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7 = 0 + 7 
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The left side equals the right side so the point (0, 7) is on the line.
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Try the last point (3, 6). You should be able to prove to yourself that the point does
NOT lie on the line because when you let x = 3 and y = 6 in the equation, both sides of
the equation are not equal. 
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Hope this helps you to understand the problem.