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I can apply one way to prove that two angles are right angles. Day 4. 4.3 A Right-Angle Theorem. If two angles were supplementary, what does this mean? If the same two angles were also congruent, what kind of angles do they have to be?. Right angle theorem.
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I can apply one way to prove that two angles are right angles. Day 4 4.3 A Right-Angle Theorem If two angles were supplementary, what does this mean? If the same two angles were also congruent, what kind of angles do they have to be?
Right angle theorem • If two angles are both supplementary and congruent, then they are right angles. (RAT) • You will not actually need to show that the angles are supplementary. Given: 1 2 Prove:
Example 1 • Given: △NOE is isosceles with base , is a median to • Prove: ∠NTO, ∠NTE are right angles N O T E
Example 2 • Given: ∠IVW is bisected, • Prove: is an altitude V W I E
Example 3 • Given: ʘO, R is the mdpt. of • Prove: O D W R
Constructions Constructing a Perpendicular Bisector