a + s = 35
25a + 15s = 675
where a = advance tickets and s = same-day tickets
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Solve for a in the first equation. Subtract s from both sides.
a = 35 - s
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Plug in a into the second equation (25a + 15s = 675).
25(35 - s) + 15s = 675
Distribute 25 inside the parentheses.
875 - 25s + 15s = 675
Combine like terms.
875 - 10s = 675
Subtract 875 from both sides.
-10s = -200
Divide both sides by -10.
s = 20
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Plug in s into the first equation (a + s = 35).
a + 20 = 35
Subtract 20 from both sides.
a = 15
✧･ﾟ: *✧･ﾟ: * :･ﾟ✧*:･ﾟ✧✧･ﾟ: *✧･ﾟ: * :･ﾟ✧*:･ﾟ✧✧･ﾟ: *✧･ﾟ: * :･ﾟ✧*:･ﾟ✧✧･ﾟ: *✧･ﾟ: * :･ﾟ✧*:･ﾟ✧
Advance tickets: $15
Same-day tickets: $20