Write it out so I can help you!
Answer:
Your answer is A 7,040 yards.
Step-by-step explanation:
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Define x:
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Let the number be x
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Construct Equation :
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x- 18 = 7x
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Take away x from both sides :
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-18 = 7x - x
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Combine like terms :
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-18 = 6x
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Switch sides :
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6x = -18
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Divide by 6 on both sides :
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x = -3
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Answer; The number is -3.
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(X,y)=(4, -1)
Hope this helps! :))