jillian is selling boxes of cookies to raise money for her basketball team. the 10 oz. box costs $3.50…

jillian is selling boxes of cookies to raise money for her basketball team. the 10 oz. box costs $3.50, while the 16 oz. box costs $5.00. at the end of one week, she collected $97.50, selling a total of 24 boxes. the system of equations that models her sales is below.\nx + y = 24\n3.50x + 5.00y = 97.50\nsolve the system of equations. how many 10 oz. boxes were sold?\n6\n9\n12\n15

jillian is selling boxes of cookies to raise money for her basketball team. the 10 oz. box costs $3.50, while the 16 oz. box costs $5.00. at the end of one week, she collected $97.50, selling a total of 24 boxes. the system of equations that models her sales is below.\nx + y = 24\n3.50x + 5.00y = 97.50\nsolve the system of equations. how many 10 oz. boxes were sold?\n6\n9\n12\n15

Answer

Explanation:

Step1: Express y in terms of x

From $x + y=24$, we get $y = 24 - x$.

Step2: Substitute y into the second - equation

Substitute $y = 24 - x$ into $3.50x+5.00y = 97.50$. $3.50x+5.00(24 - x)=97.50$.

Step3: Expand and simplify the equation

$3.50x+120 - 5.00x=97.50$. $-1.5x=97.50 - 120$. $-1.5x=-22.5$.

Step4: Solve for x

$x=\frac{-22.5}{-1.5}=15$.

Answer:

D. 15