三角形——识别全等三角形实践Problems Online

In $\triangle ABC$ above, $\angle A={66}^\circ,$ $M$ is the midpoint of side $\overline{BC},$ and $D$ and $E$ are the feet of perpendicular drawn from $M$ to $\overline{AB}$ and $\overline{AC},$ respectively. If $\lvert{\overline{MD}}\rvert=\lvert{\overline{ME}}\rvert,$ what is the measure of $\angle CME ?$

Note:The above diagram is not drawn to scale.

Triangles $ABC$ and $DEF$ are congruent, that is, $\triangle ABC \cong \triangle DEF .$ If $AB=3$ , $BC=4$ and $CA=5$ , what is the length of $DE$ ?

In triangles $ABC$ and $DEF$ , if we know that $AB = EF, BC = DE$ and $\angle ABC = \angle DEF$ , are the triangles congruent?

In triangles $ABC$ and $DEF$ , if we know that $\angle ABC = \angle DFE$ , $\angle BCA = \angle FED$ and $\angle CAB = \angle EDF$ , are the triangles congruent?

Triangles $ABC$ and $DEF$ are congruent. If $AB = DE$ , $BC = EF$ , $\angle ABC = 37 ^ \circ$ and $\angle EDF = 39 ^ \circ$ , what is the measure (in degrees) of $\angle EFD$ ?

Concept Quizzes

Challenge Quizzes

Triangles - Identify Congruent Triangles

Congruent and Similar Triangles

Concept Quizzes

Challenge Quizzes

Triangles - Identify Congruent Triangles