Print Instructions

NOTE: Only your test content will print.
To preview this answer key, click on the File menu and select Print Preview.

See our guide on How To Change Browser Print Settings to customize headers and footers before printing.

Multiplication by a Scalar

Print Answer Key (Only the test content will print)

Multiplication by a Scalar Answer Key

For [math]M = [[3,9],[5,1]][/math], what is the result of multiplying [math]M[/math] by 3?
  1. [math][[9,9],[5,1]][/math]
  2. [math][[9,27],[15,3]][/math]
  3. [math][[9,27],[5,1]][/math]
  4. [math][[9,9],[15,1]][/math]
For [math]A = [[1,7],[0,3]][/math], which of the following is equal to [math]4A ?[/math]
  1. [math][[4,28],[4,12]][/math]
  2. [math][[4,7],[0,3]][/math]
  3. [math][[4,28],[0,12]][/math]
  4. [math][[4,7],[4,3]][/math]
Find the resulting matrix if the matrix [math][[4,-2],[8,6]][/math] is multiplied by [math]3/2[/math].
  1. [math] [[6,-3],[12,9]] [/math]
  2. [math] [[12,-6],[24,18]][/math]
  3. [math] [[6,-2],[12,6]] [/math]
  4. [math] [[6,-3],[8,6]] [/math]
For [math]D = [[3, -4, 0],[2,1/2,-5]][/math], find [math]-6D[/math].
  1. [math] [[18,-4,0],[-12,1/2,-5]][/math]
  2. [math] [[18,-24,-6],[2,1/2,-5]][/math]
  3. [math] [[-18,24,0],[-12,-3,30]][/math]
  4. [math] [[18,-24,-6],[12,3,-30]][/math]
For [math]V = [[4],[-2],[8],[1/3]][/math], find [math]1/2 V[/math].
  1. [math] [[2],[-2],[8],[1/3]] [/math]
  2. [math][[2],[-1],[4],[1/6]][/math]
  3. [math] [[2],[-1],[4],[1/3]] [/math]
  4. [math] [[4],[-2],[8],[1/6]] [/math]
For [math]M = [[3,0,-9],[6,-6,12],[1,15,-3]][/math] find [math]4/3 M[/math].
  1. [math] [[4,0,-12],[6,-6,12],[1,15,-3]][/math]
  2. [math] [[4,0,-9],[8,-6,12],[4/3,15,-3]][/math]
  3. [math] [[4,4/3,-12],[8,-8,16],[4/3,20,-4]] [/math]
  4. [math] [[4,0,-12],[8,-8,16],[4/3,20,-4]] [/math]
If [math]G = [[4,5],[-2,6]][/math] and [math]a G = [[8,10],[-4,12]][/math], what is the value of [math]a ?[/math]
  1. -1/2
  2. 1/2
  3. -2
  4. 2
For [math]M = [[-12,-36,6],[-3,0,-15],[-9,24,9]][/math] and [math]a M = [[4,12,-2],[1,0,5],[3,-8,-3]][/math] , what is the value of [math]a ?[/math]
  1. [math]-3[/math]
  2. [math]-1/3[/math]
  3. [math]3[/math]
  4. [math]1/3[/math]
Matrix B is given with two of its elements unknown, [math]B = [[B_(1,1), 0],[-4, B_(2,2)]][/math]. Another matrix is given, which is matrix B which has been multiplied by a scalar, [math][[3,0],[-1,2]][/math]. What are the two unknown elements in matrix B, listed as [math]B_(1,1), B_(2,2) ?[/math]
  1. [math]12, 8[/math]
  2. [math]3/4, 1/2 [/math]
  3. [math]-12, -8[/math]
  4. [math]-3/4, -1/2 [/math]
Jason is currently in his last year of high school and is considering which university he will go to next year. He has made a matrix of his top three choices, each university in a different row, and the four most important facts for him: tuition costs per year, in dollars (first column), number of students (second column), number of faculty in his desired major (third column), and the distance from his current home, in miles (fourth column). Let this be matrix U, as follows.

[math]U = [["20,000", "30,000", 25, 30 ],["25,000", "20,000", 12, 100],["21,000", "15,000", 10, 180]] [/math]

Jason then finds out that his aunt will cover half of his tuition costs, to whatever university he wants to go to. How can Jason update matrix U with this new information using multiplication by a scalar?
  1. [math]1/2 A[/math]
  2. [math]2 A[/math]
  3. [math]A 1/2[/math]
  4. This cannot be represented with multiplication by a scalar.

Become a Help Teaching Pro subscriber to access premium printables

Unlimited premium printables Unlimited online testing Unlimited custom tests

Learn More About Benefits and Options

You need to be a member to access free printables.
Already a member? Log in for access.    |    Go Back To Previous Page