Answer:
-4
Step-by-step explanation:
-2+1= (-1) x (-1) =1 + (5x12)*60* divided by (5x3)*15* =5 -9 = -4
Tell whoever is trying to complete this problem the anwsr goes by pemdas
perenthises
exponents
multiplacation-or divistion which ever comes first
davision
addition- or subtraction whichever comes first
subtraction
Answer:
the measure of b in degrees is 32°
Answer
(a)
![A^{-1} = \frac{1}{3493} \begin{pmatrix} 210 && -59 && -12 \\ 84 && 176 && 95 \\ 77 && -5 && 295 \end{pmatrix}](https://tex.z-dn.net/?f=A%5E%7B-1%7D%20%3D%20%5Cfrac%7B1%7D%7B3493%7D%20%20%5Cbegin%7Bpmatrix%7D%20210%20%26%26%20-59%20%26%26%20-12%20%5C%5C%2084%20%26%26%20176%20%26%26%2095%20%5C%5C%2077%20%26%26%20-5%20%26%26%20295%20%5Cend%7Bpmatrix%7D)
(b)
![A^{-1} b = \begin{pmatrix} \frac{500}{7} \\\\ \frac{2400}{7} \\\\ \frac{2700}{7} \end{pmatrix}](https://tex.z-dn.net/?f=A%5E%7B-1%7D%20b%20%3D%20%5Cbegin%7Bpmatrix%7D%20%5Cfrac%7B500%7D%7B7%7D%20%5C%5C%5C%5C%20%5Cfrac%7B2400%7D%7B7%7D%20%5C%5C%5C%5C%20%5Cfrac%7B2700%7D%7B7%7D%20%5Cend%7Bpmatrix%7D)
Step-by-step explanation:
Remember that when you want to solve a problem like this, you express the equation as following
![Ax = b](https://tex.z-dn.net/?f=Ax%20%3D%20b)
So, if you know the inverse of
then
![x = A^{-1} b](https://tex.z-dn.net/?f=x%20%3D%20A%5E%7B-1%7D%20b)
For this case
![A = \begin{pmatrix} 15 && 5 && -1 \\ -5 && 18 && -6 \\ -4 && -1 && 12 \end{pmatrix}](https://tex.z-dn.net/?f=A%20%3D%20%5Cbegin%7Bpmatrix%7D%2015%20%26%26%20%205%20%26%26%20-1%20%5C%5C%20-5%20%26%26%2018%20%26%26%20-6%20%5C%5C%20-4%20%26%26%20-1%20%26%26%2012%20%20%5Cend%7Bpmatrix%7D)
Now for this case the inverse of A would be
![A^{-1} = \frac{1}{3493} \begin{pmatrix} 210 && -59 && -12 \\ 84 && 176 && 95 \\ 77 && -5 && 295 \end{pmatrix}](https://tex.z-dn.net/?f=A%5E%7B-1%7D%20%3D%20%5Cfrac%7B1%7D%7B3493%7D%20%20%5Cbegin%7Bpmatrix%7D%20210%20%26%26%20-59%20%26%26%20-12%20%5C%5C%2084%20%26%26%20176%20%26%26%2095%20%5C%5C%2077%20%26%26%20-5%20%26%26%20295%20%5Cend%7Bpmatrix%7D)
Then when you multiply with the vector solution
![A^{-1} b = \frac{1}{3493} \begin{pmatrix} 210 && -59 && -12 \\ 84 && 176 && 95 \\ 77 && -5 && 295 \end{pmatrix} * \begin{pmatrix} 2400 \\ 3500 \\ 4000 \end{pmatrix} = \frac{1}{3493} \begin{pmatrix} 249500 \\ 1197600 \\ 1347300 \end{pmatrix}\\\\\\= \begin{pmatrix} \frac{500}{7} \\\\ \frac{2400}{7} \\\\ \frac{2700}{7} \end{pmatrix}](https://tex.z-dn.net/?f=A%5E%7B-1%7D%20b%20%3D%20%20%5Cfrac%7B1%7D%7B3493%7D%20%20%5Cbegin%7Bpmatrix%7D%20210%20%26%26%20-59%20%26%26%20-12%20%5C%5C%2084%20%26%26%20176%20%26%26%2095%20%5C%5C%2077%20%26%26%20-5%20%26%26%20295%20%5Cend%7Bpmatrix%7D%20%2A%20%5Cbegin%7Bpmatrix%7D%202400%20%5C%5C%203500%20%5C%5C%204000%20%5Cend%7Bpmatrix%7D%20%3D%20%5Cfrac%7B1%7D%7B3493%7D%20%20%5Cbegin%7Bpmatrix%7D%20249500%20%5C%5C%201197600%20%5C%5C%201347300%20%5Cend%7Bpmatrix%7D%5C%5C%5C%5C%5C%5C%3D%20%5Cbegin%7Bpmatrix%7D%20%5Cfrac%7B500%7D%7B7%7D%20%5C%5C%5C%5C%20%5Cfrac%7B2400%7D%7B7%7D%20%5C%5C%5C%5C%20%5Cfrac%7B2700%7D%7B7%7D%20%5Cend%7Bpmatrix%7D)
So from that information you can conclude that the solution to the system of equations is x = 500/7 y = 2400/7 and z = 2700/7
Answer:
A is the correct one i guess... hope it helps uh