Modeling with Matrices — Unit test Answers

A cell phone carrier offers two plans for text messaging. Plan A costs $20 per month plus $0.05 per text. Plan B costs $10 per month plus $0.10 per text. For how many text messages per month are the plans the same cost?

Which classification describes the following system of equations?

What is the point of intersection when the system of equations below is graphed on the coordinate plane?

A school choir has 36 members. This year, there are three times as many returning members as new members. How many new members are in the choir this year?

Which system of equations is consistent and dependent?

The constraints of a problem are listed below. What are the vertices of the feasible region?

A school district needs to arrange transportation for at least 360 students for a field trip. The district can use large buses or small buses. The large buses hold 60 students each and have an operating expense of $300 for the day. The small buses hold 45 students each and have an operating expense of $200 for the day. The district only has chaperones for, at most, seven buses. What is the minimum cost for the transportation for the field trip if each bus has chaperones?

A total of 165 people attended the opening night of a school play. Adults were charged $6, and children were charged $2. The total amount of money collected was $618. Which augmented matrix represents the situation?

Brandi is downloading music for her MP3 player. Albums cost $10 each, and singles cost $1 each. She wants to purchase at least 5 singles but wants to spend no more than $25 total. If Brandi purchases x albums and y singles, which of the following is a possible combination of albums and singles that Brandi could purchase and stay within her guidelines?

A picture frame has a perimeter of 100 cm. Its width is 4 cm less than twice its length. What is the width of the picture frame?

Given that (3, 2, –6) and (–2, 5, 1) are solutions of two equations in a system of three linear equations, which of the following is true about the system?

Error

Galena is solving the following system.Step 1: She multiplies equation (3) by 3 and adds it to equation (1). Step 2: She multiplies equation (3) by –7 and adds it to equation (2). Which statement explains Galena’s mistake?

A local car wash is inviting customers to join the Concierge Club, in which you can have your car washed as many times as you wish for a fixed monthly fee. Amy creates the graph below to compare the cost per wash versus the cost for the Concierge Club. Which conclusion is supported by the graph?

The matrix below represents a system of equations.Which of the following describes the solution to this system of equations?