Answer :
Since it is 115, the size of the third angle would be 75 degrees.
A triangle has a sum of 180 degrees.
If two of the three angles sum up to 115, then the third angle would be 180-115 which would equal out too 75 degrees.
If two of the three angles sum up to 115, then the third angle would be 180-115 which would equal out too 75 degrees.