Answer:
![\left[\begin{array}{ccc}-25&\dfrac{75}{2}&-\dfrac{25}{2}\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-25%26%5Cdfrac%7B75%7D%7B2%7D%26-%5Cdfrac%7B25%7D%7B2%7D%5Cend%7Barray%7D%5Cright%5D)
Step-by-step explanation:
In the first equality
![5\times \left[\begin{array}{cc}-1&2\\4&8\end{array}\right] =\dfrac{2}{5}m\times \left[\begin{array}{cc}-1&2\\4&8\end{array}\right],](https://tex.z-dn.net/?f=5%5Ctimes%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D-1%262%5C%5C4%268%5Cend%7Barray%7D%5Cright%5D%20%3D%5Cdfrac%7B2%7D%7B5%7Dm%5Ctimes%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D-1%262%5C%5C4%268%5Cend%7Barray%7D%5Cright%5D%2C)
the matrices in both parts are the saem. The equality will be true if the same matrices are multiplied by the same numbers, so
![5=\dfrac{2}{5}m\Rightarrow m=5\times \dfrac{5}{2}=\dfrac{25}{2}](https://tex.z-dn.net/?f=5%3D%5Cdfrac%7B2%7D%7B5%7Dm%5CRightarrow%20m%3D5%5Ctimes%20%5Cdfrac%7B5%7D%7B2%7D%3D%5Cdfrac%7B25%7D%7B2%7D)
For the second equality
![(H+[1\ 4\ -2])+[3\ 2\ -6]=[-2\ 3\ -1]+([1\ 4\ -2]+[3\ 2\ -6]),](https://tex.z-dn.net/?f=%28H%2B%5B1%5C%204%5C%20-2%5D%29%2B%5B3%5C%202%5C%20-6%5D%3D%5B-2%5C%203%5C%20-1%5D%2B%28%5B1%5C%204%5C%20-2%5D%2B%5B3%5C%202%5C%20-6%5D%29%2C)
if
, then this equality represents the assotiative property of matrix addition.
Hence,
![m\times H=\dfrac{25}{2}\times [-2\ 3\ -1]=\left[\begin{array}{ccc}-25&\dfrac{75}{2}&-\dfrac{25}{2}\end{array}\right]](https://tex.z-dn.net/?f=m%5Ctimes%20H%3D%5Cdfrac%7B25%7D%7B2%7D%5Ctimes%20%5B-2%5C%203%5C%20-1%5D%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-25%26%5Cdfrac%7B75%7D%7B2%7D%26-%5Cdfrac%7B25%7D%7B2%7D%5Cend%7Barray%7D%5Cright%5D)
I am going to explain this using the substitution method, considering it appears to be the best in this situation.
We know (from the bottom equation) that y can equal 3x+20. Using this knowledge, we substitute the y in the top equation for 3x+20. Now, we have an equation that looks like this:
3x+20=x^2+2x
Now we need to move x to one side and then do some radicals (square roots).
Subtract the 2x on the right (since it is smaller, negatives = NONONO), which will give you
x+20=x^2
Now, we take the square root of both sides to get
rad(x+20)=x
Now we have to simplify. 20 doesn't have a square root, but 4 goes into 20, and 4 has a square root of 2. This now becomes
2rad(x+5)
This doesn't simplify any further... we have a problem... no way to isolate x as far as my knowledge goes... Sorry, can't help you any further than that, but another person or your teacher might be able to. R.I.P...
Answer:
8=58.5 9=125 10=55
Step-by-step explanation:
a triangle equals 180. so by add the angles we do know than subtracting the answer from 180. is our final answer
Answer:
Option 3: cos A=15/17
Step-by-step explanation:
Sine is the opposite side over the hypotenuse,
Cosine is the adjacent side over the hypotenuse, and
Tangent is opposite side over the adjacent side
You can remember this with the acronym SOHCAHTOA (sine, opposite, hypotenuse, cosine, adjacent, hypotenuse, tangent, opposite, adjacent)
Option 3 uses cosine, so the adjacent angle to angle A would be 15 and the hypotenuse would be 17, so 15/17
Answer:
Hi there!
The answer to this question is 177.3 ft^2
Step-by-step explanation:
You use the formula: (1/2) base one plus base two multiplied by the height
so in this case (4.7 +15) x (1/2) x 18