1. Find - 5A + 4B

A=[6, 1, - 4, - 6, 7, - 7] B=[-5, - 1, - 3, - 8, 6, 8]

a. [-10, 9, 8, - 2, 16, 67]

b. - 10, 9, 8, - 2, - 59, - 68]

c. [-50, - 9, - 1, 16, - 11, - 68]

d. [-50, - 9, 8, - 2, - 11, 67]

2. Solve the matrix equation.

2X + 2 [2, - 8, - 4, 2] = [4, - 6, 2, - 8]

a. [0, 5, - 3, - 2]

b. [0, - 11, - 3, - 6]

c. [0, 5, 5, - 6]

d. [4, 5, 5, - 2]

3. Find the product.

[-5,-2,

-8, - 5]

[-5, 7,

-9, - 5]

a. [ 25, 18, - 35, 10]

b. [43, - 25, 85, - 31]

c. [40, 45, - 56, 25]

d. [43, - 25, - 31, 85]

4. determine whether the product is defined or undefined. if defined, give the dimensions of the product matrix.

[1, 1, - 4, [9, 1, - 7]

5, 6, 0]

a. defined; 3 x 3

b. defined; 2 x 1

c. defined; 2 x 3

d. undefined

1.) A = [6, 1, - 4, - 6, 7, - 7] B = [-5, - 1, - 3, - 8, 6, 8]

-5A + 4B = - 5[6, 1, - 4, - 6, 7, - 7] + 4[-5, - 1, - 3, - 8, 6, 8] = [-30, - 5, 20, 30, - 35, 35] + [-20, - 4, - 12, - 32, 24, 32] = [-50, - 9, 8, - 2, - 11, 67]

2.) 2X + 2[2, - 8, - 4, 2] = [4, - 6, 2, - 8]

2X + [4, - 16, - 8, 4] = [4, - 6, 2, - 8]

2X = [4, - 6, 2, - 8] - [4, - 16, - 8, 4] = [0, 10, 10, - 12]

X = [0/2, 10/2, 10/2, - 12/2] = [0, 5, 5, - 6]

X = [0, 5, 5, - 6]

3.)

[-5,-2, * [-5, 7, = [25 + 18, - 35 + 10, = [43, - 25,

-8, - 5] - 9, - 5] 40 + 45, - 56 + 25] 85, - 31]

4.)

[1, 1, 4, * [9,

5, 6, 0] 1,

-7]

=> 2 x 3 * 3 x 1

since the inner dimensions is equal = 3, the product is defined and the dimension of the product is the outer dimensions 2 x 1