Question

If triangle abc is congruent with triangle DEF, then the measure of angle b is:

Which property of congruence would prove that:

Answer 1

Which property of congruence whould prove BD ≡ BD?

The triangle ABD and CBD has the same side = BD
Because they get the same side, they applied to the rule "reflexive property".
If you look at ABD, CBD, they are reflecting each other like a mirror.

The answer is first option

Answer 2

Hey! Let me help you on this one.

First of all, let's examine these two triangles.

Yes, they are indeed congruent. For example, angle $D$ is congruent to angle $A$.

In order for us to find measures of angle $B$, let's find the measure of its congruent angle - $E$

In order for us to find it, we need to know that if we add all the measures of angles, we will get 180. 

$74+50+x=180$

Now, let's solve this

$x= 180-74-50$

Simplify it.

$X= 56$

As we can see, E is set at 56 degrees, meaning that the angle congruent to it is also set at 56 degrees.

Answer: Measure of angle B is 56 degrees.