How do you simplify each expression 3-5w+12+2w-3

Express the system as AX = B; then solve using matrix inverses

Wittaler [7]

Answer with explanation:

1. The given equations are

3x -5 y=2

-x+2 y= 0

⇒The matrix in the form of , AX=B, is

$A=\left[\begin{array}{cc}3&-5\\-1&2\end{array}\right] ,\\\\ X=\left[\begin{array}{c}x&y\end{array}\right],\\\\B=\left[\begin{array}{c}2&0\end{array}\right]$

$\rightarrow X=A^{-1}B\\\\\rightarrow X=\frac{Adj.A}{|A|}\times B$

Adj.A=Transpose of cofactor of Matrix A

$Adj.A=\left[\begin{array}{cc}2&1\\5&3\end{array}\right] ,\\\\ |A|=6-5\\\\|A|=1\\\\\left[\begin{array}{c}x&y\end{array}\right]=\left[\begin{array}{cc}2&5\\1&3\end{array}\right] \times \left[\begin{array}{c}2&0\end{array}\right]\\\\x=4, y=2$

2.

The given equations are

x+y-z=2

x+z=7

2 x +y+z=13

⇒The matrix in the form of , AX=B, is

$A=\left[\begin{array}{ccc}1&1&-1\\1&0&1\\2&1&1\end{array}\right]\\\\ X=\left[\begin{array}{ccc}x\\y\\z\end{array}\right]\\\\B= \left[\begin{array}{ccc}2\\7\\13\end{array}\right]\\\\\rightarrow X=A^{-1}B\\\\\rightarrow X=\frac{Adj.A}{|A|}\times B\\\\a_{11}=-1,a_{12}=1,a_{13}=1,a_{21}=-2,a_{22}=3,a_{23}=1,a_{31}=1,a_{32}=-2,a_{33}=-1\\\\|A|=1\times(0-1)-1\times(1-2)-1\times(1-0)\\\\=-1+1-1\\\\|A|=-1\\\\Adj.A=\left[\begin{array}{ccc}-1&-2&1\\1&3&-2\\1&1&-1\end{array}\right]$

$\frac{Adj.A}{|A|}=\left[\begin{array}{ccc}1&2&-1\\-1&-3&2\\-1&-1&1\end{array}\right]\\\\X=A^{-1}B\\\\\left[\begin{array}{ccc}x\\y\\z\end{array}\right]=\left[\begin{array}{ccc}1&2&-1\\-1&-3&2\\-1&-1&1\end{array}\right]\times\left[\begin{array}{ccc}2\\7\\13\end{array}\right]\\\\x=3,y=3,z=4$

7 0

3 years ago

Filipemarcosdesouza

Margaret [11]

Answer:

noted, thanks for the note

7 0

2 years ago

Read 2 more answers

Mika rides his bike 3 miles each way to his friend's house. He leaves his house at 4 p.m. How many miles does he ride his bike t

marusya05 [52]

Answer:

How many miles does he ride his bike there and back?

6 miles.

What information is extra?

The hour at which he leaves his house.

Step-by-step explanation:

We know that he rides 3 miles each way.

Then he rides 3 miles from his house to his friend's house, and another 3 miles from his friend's house to his house.

So he rides 3 miles both times, if we add that, we get:

3 miles + 3 miles = 6 miles

So:

How many miles does he ride his bike there and back?

6 miles.

And to answer the other question, we need to look at the given information that we did not use in this calculation. In this case, is the hour at which he leaves his house.

Notice that we never did use the fact that he leaves his house at 4 p.m.

Then:

What information is extra?

The hour at which he leaves his house.

6 0

2 years ago

Determine the slope of the linear function. Y= 1/5 x + 6

Novay_Z [31]

D. 1/5

Reason: it’s always the first number in the equation

7 0

3 years ago

Read 2 more answers

5. Daniel arrives at his campsite out of breath from his swim and jog. His sister tells him that he should have swam to the boat

frosja888 [35]

Answer:

hello your question is incomplete attached below is the complete question

answer :

Daniels sister is not correct because the time that will be taken by Daniel will be greater than the initial total time taken by Daniel.

Step-by-step explanation:

First determine the time it will take Daniel to reach the Boat and the jogging time

time = distance / rate

where distance can be calculated using this equation: sin 53° = 400 / x

hence x ( distance ) = 500 ft

rate = 150

therefore Time ( t ) to reach boat = 500 / 150 = 3.33 minutes

Time for jogging ( as calculated ) = 3.69 minutes

therefore total time taken by Daniel = 3.33 + 3.69 = 7.02 minutes

Finally determine if Daniel's sister is correct that he should have swam to the boat ramp and then jogged

lets assume Distance to swim = x ( according his sister )

determine the value of x = $\sqrt{400^2 + 1400^2 }$ therefore X = 1456.02 feet

∴

Total time to be taken if Daniel follows his sister's instruction = 1456.02 / 150 = 9.71 minutes

Daniels sister is not correct because the time that will be taken by Daniel will be greater than the initial total time taken by Daniel.

6 0

2 years ago