Write a system of equations to describe the situation below, solve using an augmented matrix, and fill in the blanks.The postal service offers flat-rate shipping for priority mail in special boxes. Today, Irma shipped 1 large box, which cost her $14 to ship. Meanwhile, Britney shipped 6 small boxes and 7 large boxes, and paid $140. How much does it cost to ship these two sizes of box?Shipping costs $_____ for a small box and $_____ for a large box.
Q. Write a system of equations to describe the situation below, solve using an augmented matrix, and fill in the blanks.The postal service offers flat-rate shipping for priority mail in special boxes. Today, Irma shipped 1 large box, which cost her $14 to ship. Meanwhile, Britney shipped 6 small boxes and 7 large boxes, and paid $140. How much does it cost to ship these two sizes of box?Shipping costs $_____ for a small box and $_____ for a large box.
Set up equations: Let's set up two equations to represent the costs. Let x be the cost of a small box and y be the cost of a large box. Irma's shipment gives us the equation y=14. Britney's shipment gives us the equation 6x+7y=140.
Write system of equations: Now we'll write the system of equations:1. y=142. 6x+7y=140
Convert to matrix form: To solve using an augmented matrix, we'll convert the system of equations into matrix form. The matrix will look like this:\begin{array}{cc|c}
0 & 1 & 14 \
6 & 7 & 140
\end{array}
Eliminate variable y: We need to use the first equation to eliminate the y variable from the second equation in the matrix. But since the first equation already has y isolated and the coefficient is 1, we can just multiply the first row by −7 and add it to the second row to eliminate y from the second equation.
Perform row operation: After performing the row operation, our matrix should now look like this:0amp;1amp;∣amp;146amp;0amp;∣amp;140−(7×14)
More problems from Solve a system of equations using any method: word problems