Aldrine is buying coffee for his coworkers. He orders small and large coffees. Small coffees
cost $3 and large coffees cost $5. He spent $30 and ordered eight cups of coffee in total.
Write a system of equations that represents the situation
How many of each coffee did he buy? How do you know?

Aldrine is buying coffee for his coworkers He orders small and large coffees Small coffees cost 3 and large coffees cost 5 He spent 30 and ordered eight cups o class=

Respuesta :

Let small cups = S

Large cups = L

They bought a total of 8 cups, so S + L = 8

Rewrite as S = 8-L (1st equation)

Then you also have

$3S + $5L = $30 (2nd equation)

Replace the S in the second equation with the first equation:

$3(8-L) + $5L = $30

Simplify:

24 - 3L + 5L = 30

Combine like terms:

24+2L = 30

Subtract 24 from both sides:

2L = 6

Divide both sides by 2:

L = 3

They bought 3 large cups

Since they bought a total of 8 cups, that means they bought 5 small cups ( 8-3=5)

Large = 3 cups, Small = 5 cups