For a school fundraiser, Elena will make T-shirts. She will order T-shirts and print graphics on them. Elena must spend $349 on a printing machine and $4.80 per shirt for the blank shirts, ink, and other supplies. How much does it cost to make 40 shirts?

Hi, to answer this question we have to analyze the information given:
Printing machine cost: $349
Cost per shirt: $4.80
a)
Number of T-shirts : 20
To find the cost we have to multiply the cost of each t-shirt by the number of t-shirts, and add the cost of the machine.
cost: $349 + (20x $4.80) = $445
number of T-shirts : 40
cost : $349 + (40x $4.80) = $541
number of T-shirts : 60
cost : $349 + (60x $4.80) = $637
b) y = 349 + n (4.80)
where:
y= total cost in dollars
n = number of T-shirts