GIVEN: <3 congruent to <4, BR congruent to SD. PROVE: BIR congruent SID

Question

it's a triangle

B is on the bottom left

S is on the bottom right

R is on the bottom left after B

D is on the bottom left before S

I is at the top of the triangle

Answer 1

To prove that two angles are congruent, we need to use one of the five angle congruence postulates, such as the ASA (Angle-Side-Angle) postulate or HL (Hypotenuse-Leg) postulate.

Since <3 is congruent to <4 and BR is congruent to SD, we can use the ASA postulate: If two angles and a non-included side of one triangle are congruent to the corresponding angles and side of another triangle, then the two triangles are congruent.

Applying the ASA postulate to triangles BIR and SID, we have:

<3 = <4, BR = SD and IS is a non-included side.

Therefore, triangles BIR and SID are congruent.