Question 471925
The ordered pair consists of a value for x along with its corresponding value of y such that when those two values are substituted into the equation the left side of the equation equals the right side.
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The equation you are given is:
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y = -10x + 18
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You are also told that the value of y in the ordered pair is 78.  Substitute that value into the equation and solve for the corresponding value of x.  Substituting 78 for y results in the equation becoming:
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78 = -10x + 18
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Get rid of the 18 on the right side by subtracting 18 from both sides and you have:
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60 = -10x
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Solve for x by dividing both sides by -10 and the result is:
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-6 = x
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So now you can say that the ordered pair that makes the equation true is (-6,78).
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You can check this by returning to the original equation of:
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y = -10x +18
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and substitute -6 for x and 78 for y to get:
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78 = -10*(-6) + 18
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Do the multiplication on the right side (the minus 10 times minus 6) to get:
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78 = 60 + 18
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And the addition on the right side results in:
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78 = 78
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This means that the ordered pair (-6, 78) makes the equation true (equal on both sides) and is therefore the answer you need.
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Hope this helps you to understand the problem.