A triangle equals 180 degrees
So…
180 - 84 - 32 - 14 = 50 degrees
Then take 50/2 which equals: 25
Now add each side together:
84 + (25 + 32) + (25 + 14) = 180 degrees
Therefore ‘a’ = 25 degrees
I hope this helps, if you have any questions please comment below…