Answer: 53
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Step-by-step explanation:
let x be the number of adults and y be the number of children
The first equation is x+y = 125 since there are 125 total tickets which solves to y = -x+125 when you isolate y.
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The second equation is
9.80*x + 6.30*y = 973
because 9.80 represents the cost of 1 adult ticket and 6.30 is the cost of 1 child ticket. Also because the total sales is 973 dollars.
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Plug in y = -x+125 and isolate x
9.80*x + 6.30*y = 973
9.80*x + 6.30*( y ) = 973
9.80*x + 6.30*(-x+125) = 973 <--- y is replaced with -x+125
9.80*x - 6.30x + 787.5 = 973
3.5x + 787.5 = 973
3.5x+787.5-787.5 = 973-787.5 <--- subtract 787.5 from both sides
3.5x = 185.5
3.5x/3.5 = 185.5/3.5 <--- divide both sides by 3.5
x = 53
Therefore, 53 adult tickets were sold that day.