For the 7:30 show time, 140 movie tickets were sold. Receipts from the $13 adult tickets and the $10 senior tickets totaled $1,664. How many adult tickets and how many senior tickets were sold?

? = adult tickets? = senior tickets

We can take adult ticket as x and senior ticket as y.

Now we will form two equations

x + y = 140

13x + 10y = 1664

This system of equations we will solve using Gaussian algorithm (gradual elimination of the variables)

We will multiply first equation with (-10) and get

-10x-10y=-1400 Than we will add to second equation and get

3x=264 = > x=264/3=88 = > x=88

Now we will replace x in the first equatin before multiplying and get

88 + = 140 = > y = 140-88 = 52 = > y=52

adult tickets x=88 and senior tickets y=52

Good luck!