Measures of Interior Angles of a Triangle Sum to 180° By: Rostik and Michael.

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Presentation transcript:

Measures of Interior Angles of a Triangle Sum to 180° By: Rostik and Michael

Two-column proof This is the two-column proof When you solve you need to first give the statement and then the reasoning why is it there

Flow chart It’s almost the same as two-column proof Use same data and put into chart Use your same statements and reasons

Paragraph Use your same data and put it into paragraph Your statements and reasons Write it into the same order as you wrote your two-column proof and flow chart

Measures of Interior Angles of a Triangle Sum to 180° Adding all 3 angles to sum up to 180 degrees Finding the missing angle Solving the equation to find the angle

Adding 3 angles Add angle A, angle B, and angle C to equal 180 degrees

Two column proof 1.Triangle ABC ;AD BC 2.Angle 4 is congruent to angle 1; angle 5 is congruent to angle 2 3.Measure of angle 4 is equal to measure of angle 1; measure of angle 5 is equal to angle 2 4.Measure of angle 4 plus measure of angle BAD is equal to 180 degrees 5.Measure of angle 3 plus measure of angle 5 is equal to measure of angle BAD 6.Measure of angle 4 plus measure of angle 3 plus measure of angle 5 is equal to 180 degrees 7.Measure of angle 1 plus measure of angle 3 plus measure of angle 2 is equal to 180 degrees 1.Given 2.Alternate interior angles therom 3.Definition of congruent angles 4.Linear pair postulate 5.Angle addition postulate 6.Substitution property 7.Substitution property