ANSWER:
The equation used to represent the situation is 3x + 4y = 39.53, and Caroline spent 6.29 per lipstick.
Step-by-step explanation:
We will use x for eyeshadow and y for lipstick.
The equation would be: 3x + 4y = 39.53
3(4.79) + 4y = 39.53
14.37 + 4y = 39.53
14.37 - 14.37 + 4y = 39.53 - 14.37
4y = 25.16
4y / 4 = 25.16 / 4
y = 6.29
Check.
3x + 4y = 39.53
3(4.79) + 4(6.29) = 39.53
39.53 = 39.53
I hope this helps! :D