Answer:
x = classic lemonade cup
y = cup strawberry lemonade
In one day. Alex sells a total of 48 cups of lemonade
--->x+y=48
he won $65.75
---->1.25x+1.50y=65.75
system to solve:
x+y=48
1.25x+1.5y=65.75
by substitution: x=48-y
we replace x in the other equation:
1.25(48-y)+1.5y=65.75
60-1.25y+1.5y=65.75
0.25y=65.75-60
0.25y=5.75
y=23
he sold 23 cups of strawberry lemonade
we calculate x:
x+y=48
x+23=48
x=48-23=25
he sold 25 cups of classic lemonade