x + y = 28

y = 2x - 5

y = Marci; x = Jennifer

Jennifer and Marci are selling cookies for a fundraiser. They sold 28 boxes of cookies together. Marci sold 5 less than twice the number that Jennifer sold. How many boxes of cookies did each girl sell? Use system of equations to solve the problem.

1 answer

To solve this system of equations, we can substitute the value of y from the second equation into the first equation:

x + (2x - 5) = 28

Combining like terms:

3x - 5 = 28

Adding 5 to both sides of the equation:

3x = 33

Dividing both sides by 3:

x = 11

Now we can substitute the value of x back into the second equation to find y:

y = 2(11) - 5

y = 22 - 5

y = 17

Therefore, Jennifer sold 11 boxes of cookies and Marci sold 17 boxes of cookies.