Answer:

Step-by-step explanation:
From the question we are told that
System of equations given as
x₁ + 3x₂ + x₃ + x₄ = 3;
2x₁ - 2x₂ + x₃ + 2x₄ = 8;
x₁ - 5x₂ + x₄ = 5
Matrix form

Generally the echelon reduction is mathematically applied as

Add -2 times the 1st row to the 2nd row

Multiply the 2nd row by -1/8

Add -1 times the 2nd row to the 3rd row

Multiply the 3rd row by -8/41

Add -1/8 times the 3rd row to the 2nd row
Add -1 times the 3rd row to the 1st row

Add -3 times the 2nd row to the 1st row

Given:

To find:
The correct equivalent equation.
Solution:
We have,

Taking sin on both sides, we get

![[\because \sin (\sin^{-1}\theta )=\theta]](https://tex.z-dn.net/?f=%5B%5Cbecause%20%5Csin%20%28%5Csin%5E%7B-1%7D%5Ctheta%20%29%3D%5Ctheta%5D)
Interchanging the sides, we get

Therefore, the correct option is 4.
Answer:
C
Step-by-step explanation:
I know because i just took the test
First you would need to solve x.
2x+x+14+x-38=180
4x-24=180
4x=204
x=51
Now plug in the x for all three angle measures.
2(51)=102 degrees
51+14=65 degrees
51-38=13 degrees
Final answer is 102 degrees, 65 degrees, 13 degrees