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2 years ago

If A= and B=, find BA.

Mathematics

1 answer:

Oxana [17]2 years ago

4 0

Answer:

Option d.

Step-by-step explanation:

The given matrices are

$A=\begin{bmatrix}3&2&-4\\ \:5&-5&-3\\ \:4&1&1\end{bmatrix}$

$B=\begin{bmatrix}2&-4&1\\ \:5&-3&2\\ \:4&4&-5\end{bmatrix}$

We need to find BA.

$BA=\begin{bmatrix}2&-4&1\\ \:5&-3&2\\ \:4&4&-5\end{bmatrix}\begin{bmatrix}3&2&-4\\ \:5&-5&-3\\ \:4&1&1\end{bmatrix}$

$BA=\begin{bmatrix}2\cdot \:3+\left(-4\right)\cdot \:5+1\cdot \:4&2\cdot \:2+\left(-4\right)\left(-5\right)+1\cdot \:1&2\left(-4\right)+\left(-4\right)\left(-3\right)+1\cdot \:1\\ 5\cdot \:3+\left(-3\right)\cdot \:5+2\cdot \:4&5\cdot \:2+\left(-3\right)\left(-5\right)+2\cdot \:1&5\left(-4\right)+\left(-3\right)\left(-3\right)+2\cdot \:1\\ 4\cdot \:3+4\cdot \:5+\left(-5\right)\cdot \:4&4\cdot \:2+4\left(-5\right)+\left(-5\right)\cdot \:1&4\left(-4\right)+4\left(-3\right)+\left(-5\right)\cdot \:1\end{bmatrix}$

$BA=\begin{bmatrix}-10&25&5\\ 8&27&-9\\ 12&-17&-33\end{bmatrix}$

Hence, option (d) is correct.

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Please answer to receive ten points. I'll vote who answers first the brainliest if its correct.

beks73 [17]

The distance between points $P_1(x_1,y_1)$ and $P_2(x_2,y_2)$ can be calculated using formula

$P_1P_2=\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}.$

$AB=\sqrt{(-7-(-11))^2+(8-4)^2}=\sqrt{16+16}=\sqrt{32}=4\sqrt{2}\approx 5.657.$

$AC=\sqrt{(-4-(-11))^2+(4-4)^2}=\sqrt{49+0}=\sqrt{49}=7.$

$CB=\sqrt{(-7-(-4))^2+(8-4)^2}=\sqrt{9+16}=\sqrt{25}=5.$

Then

$P_{ABC}=5.657+7+5=17.657\approx 17.7$

Answer: correct choice is C.

3 0

2 years ago

I need some help please! ^_^

Degger [83]

Perpendicular lines will have negative reciprocal slopes. What that means is if u have a slope of 1/2, to find the negative reciprocal, flip the slope and change the sign.......flip 2/1, change the sign -2/1 or just -2. So the negative reciprocal for the slope of 1/2 is -2.

A. y = 1/5x + 3.....slope here is 1/5, so for a perpendicular line, u r gonna need an equation with the slope of -5.....and that would be : y + 3 = -5(x + 2).

B. Parallel lines will have the same slope. y = 5x - 2...the slope here is 5...so a parallel line will have a slope of 5.

y = mx + b
slope(m) = 5
(8,-2)...x = 8 and y = -2
now we sub, we r looking for b, the y intercept
-2 = 5(8) + b
-2 = 40 + b
-2 - 40 = b
-42 = b

so ur parallel equation is : y = 5x -42

7 0

3 years ago

Hi can anyone help me with this please

kupik [55]

Answer:

sure

Step-by-step explanation:

she multiplied it 3 times, so, i dont think 8 should be negative.

6 0

2 years ago

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Given the terms a10 = 3 / 512 and a15 = 3 / 16384 of a geometric sequence, find the exact value of the term a30 of the sequence.