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A Right Angle Theorem - Lesson 4.3
We started today with the following warmup problem...you should be able to come up with a diagram, the "given" and "prove" statements and the proof!! The problem was to "Prove that the median to the base of an isosceles triangle is an altitude to the base."
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In the following proof, we have to prove that two angles that are both supplementary and congruent are right angles. This is a new theorem, whose proof is shown below...it should be pretty intuitive.
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Next, we went over an example of how this theorem might be used in a
proof...there are many other examples in the homework for this
section...
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