Relationships in Triangles flashcards

0/15

15 cards remaining

Take the chapter practice test

All 15 cards in this deckShow

What do the three interior angles of any triangle add up to?Triangle Angle Sums: 180°. The three angles together form a straight angle.
How do you find the third angle of a triangle when two are known?Triangle Angle Sums: Subtract the two known angles from 180°.
How do you classify a triangle by its angles?Triangle Angle Sums: Look at the largest angle: less than 90° is acute, exactly 90° is right, more than 90° is obtuse.
What does the Exterior Angle Theorem say?Exterior Angles: An exterior angle equals the sum of the two remote interior angles.
Which angles are the remote interior angles for an exterior angle?Exterior Angles: The two interior angles not adjacent to that exterior angle.
How are an exterior angle and its adjacent interior angle related?Exterior Angles: They form a linear pair, so they add to 180°.
What does the Base Angles Theorem say about an isosceles triangle?Isosceles and Equilateral Triangles: The angles opposite the two congruent sides are congruent.
What does the converse of the Base Angles Theorem say?Isosceles and Equilateral Triangles: If two angles of a triangle are congruent, the sides opposite them are congruent.
What is true about the angles of an equilateral triangle?Isosceles and Equilateral Triangles: All three angles are congruent, and each measures 60°.
What does the Triangle Inequality Theorem say?Triangle Inequalities: The sum of any two side lengths must be greater than the third side length.
If two sides of a triangle are a and b, what lengths can the third side have?Triangle Inequalities: Strictly between the difference and the sum: |a − b| < c < a + b.
How are the side lengths and angle measures of a triangle related?Triangle Inequalities: The largest angle is opposite the longest side, and the smallest angle is opposite the shortest side.
What is true about any point on the perpendicular bisector of a segment?Perpendicular and Angle Bisectors: It is equidistant from the segment's two endpoints.
What is true about any point on an angle bisector?Perpendicular and Angle Bisectors: It is equidistant from the two sides of the angle, measured perpendicularly.
Which bisector do you use to find a point equidistant from two points, and which for two sides of an angle?Perpendicular and Angle Bisectors: Two points: the perpendicular bisector of the segment joining them. Two sides of an angle: the angle bisector.