9514 1404 393
Answer:
(x, y, z) = (-3, -1, 3)
Step-by-step explanation:
Many graphing calculators can solve matrix equations handily. Here, we use a combination of methods.
Use the last equation to write an expression for z.
z = 4 -x +4y
Substitute this into the second equation:
y -4(4 -x +4y) = -13
y -16 +4x -16y = -13
4x -15y -3 = 0
In genera form, the first equation can be written as ...
3x +y +10 = 0
Now, the solution to these two equations can be found to be ...
x = (-15(10) -1(-3))/(4(1) -3(-15)) = (-150 +3)/(4+45) = -3 . . . using "Cramer's rule"
y = -(10 +3x) = -(10 -9) = -1 . . . . from the first equation
z = 4 -(-3) +4(-1) = 3 . . . . . . . . from our equation for z
The solution to the system is (x, y, z) = (-3, -1, 3).
_____
<em>Additional comment</em>
Written as an augmented matrix, the system of equations is ...
![\left[\begin{array}{ccc|c}-3&-1&0&10\\0&1&-4&-13\\1&-4&1&4\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Cc%7D-3%26-1%260%2610%5C%5C0%261%26-4%26-13%5C%5C1%26-4%261%264%5Cend%7Barray%7D%5Cright%5D)

A=10, B=11, C=12, etc.


Now, the "only" thing that remains to do is solving the above equation.
While making this problem I only made sure it has a solution. I didn't try to solve it myself and I didn't know it will end up with such "convoluted" polynomial. Sorry to everyone who tried to solve it... m(_ _)m
I think the best way to approach it is using the rational root theorem since we know that
. Moreover we can deduce that
since there is
and
.
After you succesfully solve it, you should get the answer
.
Answer:
180
Step-by-step explanation:
Subtract the sum of the two angles from 180 degrees.