Monday

December 22, 2014

December 22, 2014

Posted by **chica** on Thursday, November 18, 2010 at 6:48pm.

Prove a triangle cannot have 2 right angles.

1) Given triangle ABC.

2) Assume angle A and angle B are both right angles is true by one of two possibilities (it is either true or false, so we assume it is true)

This is my first time to do indirect proofs, so if someone can talk me through it so I can do the next problems by myself I would be greatful.

- Geometry -
**drwls**, Thursday, November 18, 2010 at 7:35pmThe sum of the angles of a triangle must be 180 degrees. If two angles are 90 degrees, the third angle must be zero.

You need three non-zero angles to make a triangle.

Therefore a triangle cannot have two right angles.

QED

**Answer this Question**

**Related Questions**

Geometry - Write an indirect proof that an obtuse triangle does not have a right...

Math - Geometry - Two right triangles are touching at the tips. The left ...

Math(Geometry) - In the diagram below(no diagram but details will be provided), ...

Geometry - Writing indirect proofs. Can someone please check for me. I am not ...

physics and geometry - ok proving that thest two angles are equal Gesh almost ...

pls help w/t math ? - in a right triangle ABC, if ab is 14 and bc is 12 wut is ...

ALGEBRA 1 - If x and 3x-10 represent the measure of the acute angles of a right ...

GEOMETRY (Angles) PLEASE - in triangle ABC, angle b is 5 more than twice angle A...

Geometry - Given: in triangle ABC, angle B= 120 degrees Prove: angle A does not...

trig - Please answer b)only a) If a triangle has angles of 35 and 65 degrees, ...