Mathematics, 15.10.2020 05:01 jordynnmarelich9519

Here is 3 & 4 I NEED DONE ASAP!

Answers: 1

Show answers

Answers

Answer from: nelyanariba981p555ve

Given matrices are from here

link

=====================================================

Problem 3

B - C = DNE

We cannot subtract matrices of different sizes. Matrix B is 2x2 while C is 3x2. Both matrices must have the same number of rows, and they must also have the same number of columns. The matrices don't have to be square.

------------------------------

$A+B = \begin{bmatrix}-5 & 6\\7 & 4\end{bmatrix}$

You add the corresponding elements. For instance, in the top left corner we have -1+(-4) = -5. The other entries are treated in a similar manner.

------------------------------

$-2E = \begin{bmatrix}6 & -4 & 8\\-12 & 14 & -16\\-10 & -18 & 20\end{bmatrix}$

You get this from multiplying each entry in matrix E by -2. Eg: top left corner has -2*(-3) = 6

------------------------------

$CD = \begin{bmatrix}4 & 7 & 8\\ 1 & 3 & 4\\14 & 17 & 16\end{bmatrix}$

Matrix C has 3 rows and D has 3 columns. The final answer will be size 3x3

To generate each value in the answer matrix, you'll highlight rows of C to pair with columns of D. Then you'll multiply out the corresponding values, after which you add those products. This is done for every entry in the answer shown above.

For example, the first row of C is highlighted and the second column of D is highlighted. Those values pair up and multiply getting -1*(-1) + 2*3 = 1+6 = 7, which goes in the first row and second column of the answer matrix. The other entries are handled in a similar fashion.

------------------------------

$\det(B) = -46$

The 2x2 matrix determinant formula is $\begin{vmatrix}a & b\\c & d\end{vmatrix} = a*d - b*c$

In this case, a = -4, b = 6, c = 5, d = 4.

------------------------------

$B^{-1} = \begin{bmatrix}-2/23 & 3/23\\ 5/46 & 2/23\end{bmatrix}$

Swap the top left and bottom right corners of matrix B. Change the sign of the other two corner values. Then multiply each entry by 1/d where d is the determinant found back in part (e) above. Be sure to reduce any fraction as much as possible.

=====================================================

Problem 4

Answers: x = 2 and y = -10

-----------------

Work Shown:

$\begin{bmatrix}2x & 4\\-5 & -2\end{bmatrix}+\begin{bmatrix}3 & -7\\11 & y-1\end{bmatrix} = \begin{bmatrix}7 & -3\\6 & -13\end{bmatrix}\\\\\\\begin{bmatrix}2x+3 & 4+(-7)\\-5+11 & -2+(y-1)\end{bmatrix} = \begin{bmatrix}7 & -3\\6 & -13\end{bmatrix}\\\\\\\begin{bmatrix}2x+3 & -3\\6 & y-3\end{bmatrix} = \begin{bmatrix}7 & -3\\6 & -13\end{bmatrix}\\\\\\$

In the top left corners of each matrix, in line 3, we have 2x+3 = 7 which solves to...

2x+3 = 7

2x = 7-3

2x = 4

x = 4/2

x = 2

In the bottom right corners, we have y-3 = -13 which solves to....

y-3 = -13

y = -13+3

y = -10

Answer from: Quest

-7

step-by-step explanation:

x^2 + 18x + 74 = (x + 9)^2 - 81 + 74

= (x + 9)^2 - 7.

so q = -7.

Answer from: Quest

answer: a.

step-by-step explanation: the answer is a. because, you need to converge the fractions to find a solution.

Another question on Mathematics

Mathematics, 21.06.2019 21:30

Money off coupons have been circulated to 300 households. only 2/5 of these were redeemed (used) in the local supermarket to get a free shampoo. what fraction of coupons were unused? (ps: write how you got the answer)

Answers: 1

Answer

Mathematics, 22.06.2019 02:30

An incoming airplane is x miles due north from the control tower at an airport. a second incoming airplane is y miles due east of the same control tower. the shortest distance between the two airplanes is z miles. which of the following functions would best model the situation above?

Answers: 1

Answer

Mathematics, 22.06.2019 07:20

Bill earns $12 per hour and works at most 40 hours per week. identify the independent and dependent quantity in the situation, and find reasonable domain and range values

Answers: 3

Answer

Mathematics, 22.06.2019 09:00

Ajar holds no more than 500 buttons. if 5 people bring 330 buttons each, how many jars are necessary to hold all of the buttons?

Answers: 1

Answer

You know the right answer?

Here is 3 & 4 I NEED DONE ASAP!
...

Questions