Definitions

Definitions

Name the Theorem

Find the Angles

Are they Congruent?/Reason

Miscellaneous

100

A triangle with two congruent sides

What is an isosceles triangle?

100

The sum of the measures of the interior angles of a triangle is 180

What is the Triangle Sum Theorem?

100

See diagram #1.
The measure of angle 1 is ___
The measure of angle 2 is ___
The measure of angle 3 is ___

What are 50, 40 and 45?

200

In a right triangle, the sides that form the right angle are the ___ and the side opposite the right angle is the ___.

What are the legs and hypotenuse?

200

The measure of an exterior angle of a triangle is equal to the sum of the measures of the two nonadjacent interior angles

What is the Exterior Angle Theorem?

200

See Diagram #2
The value of x is ___

What is 39?

300

A statement that can be proved easily using a theorem.

What is a corollary?

300

If two angles and a nonincluded side of one triangle are congruent to two angles and the corresponding nonincluded side of a second triangle, then the two trianlges are congruent.

What is the Angle-Angle-Side Theorem?

300

See Diagram #3
The value of x is ___

What is 12?

400

When the sides of a triangle are extended, the three original angles are the ___ and the angles adjacent to them are the ___.

What are interior angles and exterior angles?

400

If two sides of a triangle are congruent, then the angles opposite them are congruent

What is the Base Angles Theorem?

400

See diagram #4
The value of x is ___
The value of y is ___

What are 54 and 63?

500

Two figures are congruent when there is a correspondence between their angles and sides such that ___ are congruent and ___ are congruent.

What are corresponding angles and corresponding sides?

500

If the hypotenuse and a leg of a right triangle are congruent to the hypotenuse and a leg of a second triangle, the the two right triangles are congruent?

What is the Hypotenuse-Leg Theorem?

500

See Diagram #5
The value of x is ___
The value of y is ___

What are 30 and 120?

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