The value of 'x' is 10°
We have that supplementary angles sum up to 180
M∠A = (6x +4)° and m∠B = (10x + 16)°.
Then,
6x + 4 + 10x + 16 = 180
Collect like terms
16x + 20 = 180
16x = 180 - 20
16x = 160
x = 160/ 16
x = 10°
Thus, the value of 'x' is 10°
Learn more about supplementary angles here:
https://brainly.com/question/2046046
#SPJ1