## somebodys_heartbrake 2 years ago Find c if a = 7 and b = 9. Right triangle with sides a, b, and c. Side c is opposite the right angle. A. c = 16 B. c = 4 C. c = 3 times the square root of 7 D. c = the square root of130

1. somebodys_heartbrake

2. RandomFriend

Use the pythagoreon theroem!

3. RandomFriend

Did you? What's up? Let's Math.

4. somebodys_heartbrake

um like this A^2 +B^2= C^2

5. RandomFriend

You got it. You are given A and B. Let's do it. 7^2 + 9^2 = C^2.

6. somebodys_heartbrake

49+81

7. Azteck

@somebodys_heartbrake that's exactly the same question as the previous one except this one has different values. And now you don't know square roots and squaring which should of been taught in primary/elementary school.

8. RandomFriend

Sweet whats 49+81?

9. AravindG

sweet? o.O

10. somebodys_heartbrake

130

11. RandomFriend

Alright so far we know that 130 = C^2. What's C???

12. AravindG

@Azteck you are right infact i had replied in previos question and when i saw this i thought my reply got deleted :O .

13. Azteck

I think it's a different question, but then it's just using the same format as the previous one.

14. RandomFriend

Alright so far we know that C^2 = 130. Let's find C. Do you know how to find square roots, or are you a little bit rusty?

15. somebodys_heartbrake

idk sorry

16. RandomFriend

Do you know the square root of say 9? Or do you know nothing about square roots? I don't care either way so just be honest

17. RandomFriend

$\sqrt{9}$

18. somebodys_heartbrake

idk :/

19. RandomFriend

haha alright :) Let's learn some square roots then. I'm not a math teacher but i'll try my best.

20. somebodys_heartbrake

ok thanks for helping btw

21. RandomFriend

So basically a square root is " What number multiplied by itself will give me this number"

22. AravindG

@RandomFriend i appreciate your effort to help the asker get to the answer ..make sure you do not spoonfeed anyone in the process ,happy studying! :)

23. RandomFriend

@AravindG Thanks! Happy internet moderating.

24. RandomFriend

Anyway another way to look at square roots is "What number SQUARED, equals this number?" So lets look at $\sqrt{4}$ . 2 squared . Aka 2*2 = 4

25. somebodys_heartbrake

wouldnt it be 3 to the first 1 u asked

26. RandomFriend

Yeah exactly. 3*3 = 9. So the square root of 9 is three.

27. somebodys_heartbrake

ok

28. RandomFriend

Alright it works with letters or "variables" too. What's the square root of $\sqrt{x^2}$ ?

29. somebodys_heartbrake

x?

30. RandomFriend

Nice. X*X = X^2. How about something that applies to us. What is the $\sqrt{C^2}$

31. somebodys_heartbrake

c

32. AravindG

well done @somebodys_heartbrake and @RandomFriend :)

33. RandomFriend

Nailed it. So we left off at $C^2 = 130$. What happens if we take the square root of both sides?

34. somebodys_heartbrake

um not sure

35. RandomFriend

Write it out for me. Put a square root symbol around both sides.

36. somebodys_heartbrake

idk how to do that

37. AravindG

......................

38. RandomFriend

Alright so we are just going to draw a square root sign around both sides. You can do it. I'll do it first. $\sqrt{C^2} = \sqrt{130}$

39. AravindG

@somebodys_heartbrake please make a thorough reading on this tutorial http://www.mathsisfun.com/square-root.html

40. Azteck

@somebodys_heartbrake wants to know how to write a square root sign like what @RandomFriend did above. I don't think @somebodys_heartbrake knows how to use the equation editor.

41. RandomFriend

I dont care if you don't know how to use the equation thing. As long as you get it. Do you see how i got my equation above?

42. RandomFriend

Alright I'ma move on. from here $\sqrt{C^2} = C.$. This givese us C = sqrt(130). Which was one of our answers I believe.