Answer:
d) 10°
Step-by-step explanation:
The sum of supplementary angles always equal 180°.
Since two angles are supplementary, the two angles must add up to equal 180°. Angles A and B are known, so the equation is as follows.
[tex]A + B = 180\\(6x + 4) + (10x + 16) = 180\\\\[/tex]
Rearrange and combine like terms:
[tex]6x + 10x + 16 + 4 = 180\\16x + 20 = 180\\[/tex]
Isolate x:
[tex]16x = 180 - 20\\16x = 160\\x =10[/tex]
