Help plz:))) I’ll mark u brainliest

In-s [12.5K]

ANSWER

24

EXPLANATION

For a matrix A of order n×n, the cofactor $C_{ij}$ of element $a_{ij}$ is defined to be

$C_{ij} = (-1)^{i+j} M_{ij}$

$M_{ij}$ is the minor of element $a_{ij}$ equal to the determinant of the matrix we get by taking matrix A and deleting row i and column j.

Here, we have

$C_{11} = (-1)^{1+1} M_{11} = M_{11}$

M₁₁ is the determinant of the matrix that is matrix A with row 1 and column 1 removed. The bold entries are the row and the column we delete.

$\begin{aligned} A=\begin{bmatrix} \bf 1 & \bf -6 & \bf -4\\ \bf 7 & 0 & -3 \\ \bf -9 & 8 & -8 \end{bmatrix} \implies M_{11} &= \text{det}\left(\begin{bmatrix} 0&-3 \\ 8&-8 \end{bmatrix} \right) \end{aligned}$

Since the determinant of a 2×2 matrix is

$\det\left( \begin{bmatrix} a & b \\ c& d \end{bmatrix} \right) = ad-bc$

it follows that

$\begin{aligned} A=\begin{bmatrix} \bf 1 & \bf -6 & \bf -4\\ \bf 7 & 0 & -3 \\ \bf -9 & 8 & -8 \end{bmatrix} \implies M_{11} &= \text{det}\left(\begin{bmatrix} 0&-3 \\ 8&-8 \end{bmatrix} \right) \\ &= (0)(-8) - (-3)(8) \\ &= -(-24) \\ &= 24 \end{aligned}$

so $C_{11} = M_{11} = 24$

4 0

3 years ago

Why is dividing a fraction by 3 and then multiplying by 2 the same as multiplying by 2/3?

Tema [17]

It would be the same you would already be dividing by 3 because it’s the denominator and the numerator is 2

7 0

2 years ago

Now use the distributive property to factor the expression you obtained in part D??????

Step2247 [10]

Answer:

150 + 2x

The greatest common factor of 150 and 2x is 2. Factor out a 2 from both terms:

2(75) + 2(x).

Use the Distributive Property, A(B + C) = AB + AC, to rewrite the expression:

2(75 + x).

The expression 150 + 2x is equivalent to 2(75 + x).

Step-by-step explanation:

Might want to change it up a bit bc thats the exact answer. Hope that helps

8 0

3 years ago

Read 2 more answers

Evaluate the expression 81-8^2

Tpy6a [65]

Answer:

17

Step-by-step explanation:

Do the exponent first, then subratct it to 81

7 0

3 years ago

Dafes stickball team has six players.how many different six player battling lineups can they make ifdave must bat second and eit

aalyn [17]

Let us name the players A,Dave,Zack,Paul,E and F
For the first position there are two candidades ( Zack / Paul )
For the second position there is only one candidate i.e. Dave
For the third place there will be 4 candidates (out of Zack and Paul - 1 as one of them is already taken for the first position and A, E and F total-4)
For the fourth place there will be 3 candidates ( out of the four available candidates in the 3rd place, one will be taken up for 3rd place )
For the fifth place there will be 2 candidates
Finally, for the last place there will be only one candidate left.
On multiplying the no. of available cadidates, we get 2 * 1 * 4 * 3 * 2 * 1 = 48 i.e. option (A)
Please mention minor spelling mistakes
For the second question:
Let the no of dotted marbles be 'x' and no of striped marbles be 'y'
then the equation will become as follows
(y+6)/x = 3
and
(x+6)/y = (2/3)
On solving the equations, we will get x = 10 and y = 24
Total balls = 10+24+6 = 40 (option E)
Answer 3 will be ) For the first edge, he can choose 3 paths
For the second edge he can choose 2 paths for each path of its first edge's path
For the third , he is bounded to move on the paths created by the first and the second edges hence 1 path for each path created by the first and the second edge together
It will be multiplication of all the possibilities of the paths of the three edges differently.........
i.e. 3 * 2 * 1 = 6

6 0

3 years ago