Atotal of 273 tickets were sold for the school play. they were either adult tickets or student tickets. the number of student tickets sold was two times the number of adult tickets sold. how many adult tickets were sold?

X = adult tickets
y = student tickets
x + y = 273
2x = y

In order to solve this, use substitution:
x + 2x = 273
3x = 273 (divide by 3 on both sides)
x = 91 adult tickets

If you want to check your answer, plug in your answer into the second equation and then use both answers for the first equation:
2x = y
2(91) = y
y = 182 student tickets
x + y = 273
91 + 182 = 273
273 = 273 (If both sides are the same value, this means your answer is correct.)

Best of luck, friend. 

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