Answer:
![6A- 8B = \left[\begin{array}{ccc}56&50&-14\\-126&92&62\\-78&26&2\end{array}\right]](https://tex.z-dn.net/?f=6A-%208B%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D56%2650%26-14%5C%5C-126%2692%2662%5C%5C-78%2626%262%5Cend%7Barray%7D%5Cright%5D)
Option A is correct.
Step-by-step explanation:
![A=\left[\begin{array}{ccc}-4&-1&-9\\-9&6&9\\-1&-1&3\end{array}\right] \\B=\left[\begin{array}{ccc}-10&-7&-5\\9&-7&-1\\9&-4&2\end{array}\right]](https://tex.z-dn.net/?f=A%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-4%26-1%26-9%5C%5C-9%266%269%5C%5C-1%26-1%263%5Cend%7Barray%7D%5Cright%5D%20%5C%5CB%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-10%26-7%26-5%5C%5C9%26-7%26-1%5C%5C9%26-4%262%5Cend%7Barray%7D%5Cright%5D)
We need to find 6A - 8B
Multiply matrix A with 6 and matrix B with 8 and then subtract 6A - 8B
![6A=\left[\begin{array}{ccc}-24&-6&-54\\-54&36&54\\-6&-6&18\end{array}\right] \\8B=\left[\begin{array}{ccc}-80&-56&-40\\72&-56&-8\\72&-32&16\end{array}\right]\\6A - 8B =\left[\begin{array}{ccc}-24-(-80)&-6-(-56)&-54-(-40)\\-54-(72)&36-(-56)&54-(-8)\\-6-(72)&-6-(-32)&18-(16)\end{array}\right] \\6A - 8B =\left[\begin{array}{ccc}-24+80&-6+56&-54+40\\-54-72&36+56&54+8\\-6-72&-6+32&18-16\end{array}\right] \\6A- 8B = \left[\begin{array}{ccc}56&50&-14\\-126&92&62\\-78&26&2\end{array}\right]](https://tex.z-dn.net/?f=6A%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-24%26-6%26-54%5C%5C-54%2636%2654%5C%5C-6%26-6%2618%5Cend%7Barray%7D%5Cright%5D%20%5C%5C8B%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-80%26-56%26-40%5C%5C72%26-56%26-8%5C%5C72%26-32%2616%5Cend%7Barray%7D%5Cright%5D%5C%5C6A%20-%208B%20%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-24-%28-80%29%26-6-%28-56%29%26-54-%28-40%29%5C%5C-54-%2872%29%2636-%28-56%29%2654-%28-8%29%5C%5C-6-%2872%29%26-6-%28-32%29%2618-%2816%29%5Cend%7Barray%7D%5Cright%5D%20%5C%5C6A%20-%208B%20%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-24%2B80%26-6%2B56%26-54%2B40%5C%5C-54-72%2636%2B56%2654%2B8%5C%5C-6-72%26-6%2B32%2618-16%5Cend%7Barray%7D%5Cright%5D%20%5C%5C6A-%208B%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D56%2650%26-14%5C%5C-126%2692%2662%5C%5C-78%2626%262%5Cend%7Barray%7D%5Cright%5D)
So,
Option A is correct.
Answer: 79,200 feet
Step-by-step explanation:
15 x 5,280= 79,200
Answer:
C. In eight years the computer will have no value.
A. When new the computer was worth $3,000.
Step-by-step explanation:
Here, we need to construct 2 linear equation.
Let x be the plate and y be the cup.
1) 4x + 3y = 20.70
2) 5x + 4y = 26.40
From equation 1, we solve for y.
3y = 20.70 - 4x
y = (20.70 - 4x) / 3
Substitute into equation 2.
5x + 4((20.70 - 4x) / 3) = 26.40
5x + 27.60 - 5.33x = 26.40
-0.33x = 26.40 - 27.60
-0.33x = -1.2
x = 3.64
We already get value of x. Now, calculate for value of y.
y = (20.70 - 4x) / 3
y = (20.70 - 4(3.64)) / 3
y = 2.05
The cost for 1 plate is 3.64 dollars and 1 cup is 2.05 dollars.
Answer:
3rd one?
Step-by-step explanation:
