Determinants — Unit test Answers

Each column of the matrix represents a vertex of a rectangle on the coordinate plane. If Fan scales the rectangle by finding 4A, what are the vertices of the scaled rectangle?

Jim’s family is choosing whether to go to a restaurant for lunch or for dinner. The cost of a salad is $7 at lunch and $9 at dinner. The cost of a steak is $10 at lunch and $12 at dinner. Each person will choose either a salad or a steak regardless of the mealtime. Jim calculates the food bill to be $41 if they go during lunch and $51 if they go during dinner. How many people will choose a salad?

What is the value of given the matrix equation below?

Matrix C is a transformation of matrix B, and matrix B is a transformation of matrix A, as shown below.Which matrix represents matrix C?

Using Cramer’s Rule, what is the value of x in the solution to the system of linear equations below?

The matrix below represents a system of equations.What is the solution to this system of equations?

What is the product?

The tables below show running hours of three printers that produce greeting cards and the total number of greeting cards produced over three weeks. Number of Hours Machine Is Running Printer APrinter BPrinter CWeek 1405045Week 2455035Week 3504050 Total Cards ProducedWeek 17,950Week 27,350Week 38,700Printer B uses $15 in ink every hour. What is the ink cost for each card coming from printer B?

Raj encoded a secret phrase using matrix multiplication. Using A = 1, B = 2, C = 3, and so on, he multiplied the clear text code for each letter by the matrix to get a matrix that represents the encoded text. The matrix representing the encoded text is . What is the secret phrase? Determine the location of spaces after you decode the text.

Using Cramer’s Rule, what is the value of y for the solution to the system of linear equations below?

Suppose matrix D is the inverse of matrix C. Which of the following is equal to D?

Jonas made the following matrix of temperatures for the first 4 days of January. He also made the following matrix of temperatures for the first 4 days of February. Which matrix shows the difference of January and February?

What are the values of c and d in the matrix subtraction below?

Using Cramer’s Rule, what is the value of x in the solution to the system of equations below?

What is the product?