Question 953527
A room contains 78 chairs arranged in rows. The number of rows is one more than twice the number of chairs per row. Find the number of rows.
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Let the number of rows be "r".
Let the number of chairs in a row be "c"
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Equations:
c*r = 78
r = 2c+1
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Substitute for "r" and solve for "c":
c(2c+1) = 78
2c^2 + c - 78 = 0
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Factor:
(c-6)(2c+13) = 0
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Positive solution:
# of chairs in a row = 6
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Solve for "r":
r = 2c+1
# of rows = 2*6+1 = 13
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Cheers,
Stan H.
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