Solve real world problems with a system of linear equations
A burger place sells burgers (b) for $4, and fries (f) for $2. If bob bought six items for a total of $18, how many did he buy of each?
A system of linear equations can be used to solve this problem.
Let b be the number of burgers bob bought
Let f be the number of orders he placed for French fries
Then, we can come up with the following two equations
4b + 2f = 18 (equation 1)
b + f = 6 (equation 2)
Solve for b in equation 2. We can do this by subtracting f from both sides of the equation
b + f - f = 6 - f
b = 6 - f
Replace b with 6 - f in equation 1
4 (6 - f) + 2f = 18
4x6 - 4xf + 2f = 18
24 - 4f + 2f = 18
24 - 2f = 18
24 - 18 = 2f
6 = 2f
f = 3
Since b = 6 - f, b = 6 - 3 = 3
Therefore, Bob ordered 3 items each
Click here to post comments
Join in and write your own page! It's easy to do. How? Simply click here to return to System of linear equations.
Mar 13, 19 11:50 AM
Learn how to derive the equation of an ellipse when the center of the ellipse is at the origin.
New math lessons
Your email is safe with us. We will only use it to inform you about new math lessons.