SOLUTION: 1. Can a triangle have two obtuse angles? Justify your answer

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Question 180206: 1. Can a triangle have two obtuse angles? Justify your answer
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
No.
The sum of the 3 angles of a triangle equals 180.
1.A%2BB%2BC=180
If two angles (A,B) are greater than 90, then their sum would be greater than 180.
A%2BB=180%2BDELTA
where DELTA is some arbitrarily small positive amount.
Then substituting into eq. 1,
1.A%2BB%2BC=180
180%2BDELTA%2BC=180
DELTA%2BC=0
C=-DELTA
We've shown that the remaining angle (C) would need to be negative to make the sum equal 180.
That's not possible, therefore two obtuse angles would not be allowed in a triangle.