The cost of a lemonade is $1.5 while that of a cookie is $0.75.
An equation is an expression used to show the relationship between two or more variables and numbers.
Let x represent the cost of a lemonade and y represent the cost of a cookie, hence:
9x + 11y = 21.75 (1)
Also
22x + 14y = 43.50 (2)
From equation 1 and 2:
x = 1.5, y = 0.75
The cost of a lemonade is $1.5 while that of a cookie is $0.75.
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