David W. answered 07/02/15
Tutor
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The problem asks that we find $ for adult ticket (A) and for child ticket (C). And, Dollars = number of tickets* ($/ticket)..
First day: 7A + 5C = 119 or 63A + 45C = 1071 (multiplied by 9)
Second day: 9A + 4C = 136 or 63A + 28C = 952 (multiply by 7)
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0 + 17C = 119 (subtract equations)
C = $7 (divide both sides by 17)
7A + 5(7) = 119 (put C=7 into first equation)
7A = 84 (subtract 35 from both sides)
A = $12 (divide both sides by 7)
Check:
Is 7(12) + 5(7) = 119 ?
84 + 35 = 119 ? yes
Is 9(12) + 4(7) = 136 ?
108 + 28 = 136 ? yes