x= # of hamburgers
x-74= # of cheeseburgers
Add both x and (x-74) together equal to the total number of hamburgers and cheeseburgers sold.
x + (x - 74)= 576
combine like terms
2x - 74= 576
add 74 to both sides
2x= 650
divide both sides by 2
x= 325 hamburgers
Substitute x=325 to find # of cheeseburgers.
=x-74
=325-74
= 251 cheeseburgers
CHECK:
325 + 251= 576
576= 576
ANSWER: There were 325 hamburgers sold.
Hope this helps! :)
