a movie theater charges 7.00 for adults and 4.25 for children. during a recent trip 139 tickets were sold for a total of $720. How many of adult tickets and children tickets were sold. respectively?

Answer 1

a + c = 139

7a + 4.25c = 720

We can do this two ways when I look at it.

First, solve for either a or c and substitute. I'll do a.

a = 139 - c

7(139 - c) + 4.25c = 720

973 - 7c + 4.25c = 720

-2.75c = -253

c = 92

a = 139 - 92

a = 47

Orrrrr, we can make opposites by multiplying the 1st equation by -7 or -4.25. I'll do 7.

-7a - 7c = -973

7a + 4.25c = 720

Adding the two equations together...

-2.75a = -253

Solve the rest like the 1st example.