On tuesday, a local hamburger shop sold a combined total of 240 hamburgers and cheeseburgers. the number of cheeseburgers sold was two times the number of hamburgers sold. how many hamburgers were sold on tuesday?

120 hamburgers

Step-by-step explanation:

240÷2=120

120•2=240

yes because there is exactly one y value for every x value

for function there can't be more than one value for every x value

n=9

step-by-step explanation:

7 times a number = 7n

decreased by 13 = 7n-13

same as is =

5 times the number = 5n

increased by 5 = 5n+5

7n-13 = 5n+5

2n=18

n=9