Algebra word problem help

Question

dev purchased tickets to an airshow for 3 adults and 5 children and the total cost was $128. Susan purchased tickets for 4 adults and 6 children to the same airshow for $161. What was the price of a single adults ticket?

Answer 1

Let a = adult ticket pice

Let c = child ticket price

 

3a + 5c = 128

4a + 6c = 161

 

You want the price of an adult ticket so let's eliminate

the c variable.  Multiply equation 1 through by -6 and

multiply 2nd equation through by 5, then add them.

 

-18a - 30c = -768

20a + 30c = 805

----------------------

2a =37

a = $18.50