SOLUTION: A. Directions. Use indirect proof to prove each statement. Write your answer on a separate sheet of paper.
2. In ∆ABC, if B is a right angle,
Prove that A cannot be obtuse
Algebra ->
Equations
-> SOLUTION: A. Directions. Use indirect proof to prove each statement. Write your answer on a separate sheet of paper.
2. In ∆ABC, if B is a right angle,
Prove that A cannot be obtuse
Log On
Question 1176926: A. Directions. Use indirect proof to prove each statement. Write your answer on a separate sheet of paper.
2. In ∆ABC, if B is a right angle,
Prove that A cannot be obtuse
Assume angle A is obtuse. Then the measure of angle A is greater than 90 degrees. Since angle B is right, the measure of angle B is 90 degrees. Then, regardless of the measure of angle C, the sum of the three angles is greater than 180 degrees. This contradicts the fact that the sum of the angles of any triangle is 180 degrees. Therefore the initial assumption is false -- Angle A is not obtuse (nor is it right for that matter).
John
My calculator said it, I believe it, that settles it
From
I > Ø
