Answer:
a = 43°
Step-by-step explanation:
The sum of the 3 angles in a triangle = 180°
Sum the 3 angles and equate to 180, that is
a + 8 + 2a + 43 = 180
3a + 51 = 180 ( subtract 51 from both sides )
3a = 129 ( divide both sides by 3 )
a = 43
