## pooja195 one year ago Can some please explain how to do #37 to me.... i'm not really sure how. http://prntscr.com/8dqn9t

1. Hero

@pooja195, do you remember the acronym for congruent triangles?

2. pooja195

No :/

3. Hero

You don't remember what CPCTC stands for?

4. pooja195

Corresponding parts of a triangle are congruent...? right?

5. Hero

Correct, Corresponding parts of congruent triangles are congruent. What do you think this means for $$\triangle{ABC} \cong \triangle{DEF}$$ ?

6. pooja195

that equal sign with the squiggly thingy means that they correspond so triangle ABC corresponds to triangle DEF?

7. dan815

it means congruent or equal trinagles

8. pooja195

same thing -.-

9. Hero

Well, @pooja195, here's a bit of insight for you: $$\triangle{ABC} \cong \triangle{DEF}$$ means the following: $$\angle{A} \cong \angle{D}$$ $$\angle{B} \cong \angle{E}$$ $$\angle{C} \cong \angle{F}$$ $$\overline{AB} \cong \overline{DE}$$ $$\overline{BC} \cong \overline{EF}$$ $$\overline{AC} \cong \overline{DF}$$

10. pooja195

this is confusing... :/

11. Hero

The corresponding angles have the same measure and the corresponding segments have the same length.

12. pooja195

So DEF is 5?

13. Hero

I think what you meant to say is that since $$\overline{AC} = 5$$ then $$\overline{DF} = 5$$

14. Hero

@pooja195, what does the problem ask us to find?

15. pooja195

Find DF and m<B

16. Hero

Okay, and we found $$\overline{DF}$$. Now we have to find $$m\angle{B}$$. Any ideas on that at all based on what was explained above?

17. pooja195

B and E are congruent

18. Hero

B and E correspond with each other and therefore have the same measure.

19. pooja195

so 100 degrees?

20. Hero

$$m\angle{E} = 100^{\circ}$$, therefore $$m\angle{B} = 100^{\circ}$$. That's how you would say it properly. Saying just "100 degrees" isn't really saying anything other than just "announcing" 100 degrees. Somebody might think you're referring to the temperature outside.

21. pooja195

Aight thanks :)