Answer:
12
Step-by-step explanation:
So she went there 4 times. Each time, she pays for the salad itself (we don't know how much) and she also leaves a 1,50 dollar tip. All together, she paid 54 dollars.
-> TIPS: 4x 1,50= 6 (dollars)
-> SALADS: 54 (total amount she paid) - 6 (tips) = 48 (all the 4 salads she bourght)
-> 1 SALAD: 48/4=12
-----------linear equation:-------------
54 = 4 x 1,5 + 4 x c
54 = 6 + 4c
48 = 4c
12 = c
