word problem

Question

a factory assembly 4-cylinder and 6-cylinder engines . how many motors of each kind must the factory make to fill an order for 20 engines with a total of 92 cylinders ?

 

Answer 1

4x+6y=92

x+y=20

x=20-y

4(20-y)+6y=92

80-4y+6y=92

80+2y=92

2y=92-80

2y=12

y=6 6-cylider engines

x=20-6=14 4-cylinder engines