Solve using cramers rule

Question

tickets of a program at college cost 4 for general admission or 3 with a student id if 174 people paid to see a performance and 611 was collected how many of each type of ticket were sold

Answer 1

x = tickets sold at general admission

y = rickets sold at student ID price

 

($4)x + ($3)y = $611

x + y = 174

 

Solve this system for x and y:

 

4x + 3y = 611

x + y = 174

 

D = |4 3| = 4(1) - 3(1) = 1

      |1 1|

 

D_x = |611  3| = 611(1) - 174(3) = 89

        |174  1|

 

D_y = |4  611| = 4(174) - 1(611) = 85

        |1  174|

 

x = D_x/D = 89/1 = 89

y = D_y/D = 85/1 = 85