Answer:
She bought 86 child tickets and 14 adult tickets.
Explanation:
14x+19y=1470
x+y=100
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14x+19y=1470
-14(x+y=100)
--------------------------
14x+19y=1470
(+) -14x-14y=-1400
+19y=1470
-14y=-1400
5y=70
y=14
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x+14=100
x=86