Answer:
C. x = 42
Step-by-step explanation:
First we need to use the triangle sum theorem to find the measure of the third angle of the triangle.
180 = 126 + 16 + y
180 = 142 + y
y = 38
Now that we found that, we can then figure out the measure of x, knowing that the three angles make a straight angle, which is 180°
180 = 16 + 38 + 3x
180 = 54 + 3x
126 = 3x
x = 42
The value of x is 42.