Two angles (a + 31) and (b – 49o) are adjacent angles on a straight line. Which of the following is true
-
A.
a + b = 198o -
B.
a + b = 180o -
C.
a + b = 162o -
D.
a + b = 100o -
E.
a + b = 80o
Correct Answer: Option A
Explanation
a + 31 + b – 49 = 180o(sum of angles on str line)
a + b – 18 = 180o
a + b = 180 + 18
a + b = 198o