Answer:
Step-by-step explanation:
Let a and c represent the costs of adult and child tickets, respectively. Then the two purchases can be described by ...
2a +4c = 46 . . . . . . Sue's purchase
4a +7c = 86 . . . . . . Karen's purchase
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The system can be solved by subtracting the second equation from twice the first:
2(2a +4c) -(4a +7c) = 2(46) -(86)
c = 6 . . . . . . . simplify
We can substitute this value into half the first equation to find "a".
a +2(6) = 23
a = 23 -12 = 11
The cost of 1 adult ticket is $11; the cost of one child ticket is $6.
