## hal_stirrup 3 years ago factor out this> x^4 -25 explain the answer if you could plz. thanks

1. telliott99

difference of squares a^2 - b^2 = (a + b)(a - b)

2. hal_stirrup

thanks . solve it plz

3. telliott99

Oh, I think you can do sqrt(x^4), and sqrt(25)

4. ParthKohli

@hal_stirrup Did you understand?

5. ParthKohli

Can you tell what $$\sqrt{25}$$ and $$\sqrt{x^4}$$ are?

6. best.shakir

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7. best.shakir

1 min i will explain

Find the square root of x^4 and 25 = x^2 and 5 Difference of squares: (a+b)(a-b) (x^2-5)(x^2+5)

You can use FOIL to expand it back out and you will get x^4-25

10. hal_stirrup

thanks .

11. koli123able

then either at x^2=5 or x^2=5

12. koli123able

sorry it will be x^2=5 or x^2=-5

13. koli123able

on squaring in x^2=5 the value of x will be 25

14. koli123able

and on squaring x^2=-5 the value of x will be the same 25

15. hal_stirrup

thanks @koli123able.

16. hal_stirrup

how did you get to x^2=5 or x^2=-5 explain plz. thanks

17. koli123able

18. koli123able

ANYONE THERE

19. hal_stirrup

yes

20. hal_stirrup

please take it from the top.

21. koli123able

x^4-25

22. koli123able

sorry i type too wrong

23. koli123able

(x)^2 - (5)^2

24. koli123able

opening it by formula (a - b)^2

25. hal_stirrup

you squared it!

26. koli123able

(x-5)^2

27. koli123able

take 2 power common

28. hal_stirrup

sure

29. koli123able

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30. koli123able

now

31. koli123able

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32. koli123able

ohhhhh my gooodddddd i am doing it wrong

33. koli123able

sorry from the top

34. hal_stirrup

take you time :)

35. koli123able

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36. koli123able

did u get it till here

37. hal_stirrup

yes. thanks

38. koli123able

now u can solve it further but this answer is absoluteley right

39. hal_stirrup

so what about "x^2=5 or x^2=-5 "

40. koli123able

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41. koli123able

suppose it as an equation in some parts of world they solve it by this too

42. hal_stirrup

but this is am expression!! dose that last bit matter?

43. koli123able

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44. hal_stirrup

45. koli123able

the whole asked to factorize the result is at the top but if someone says factorize and get the values of variable then u need to get a bit further

46. koli123able

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47. koli123able

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48. hal_stirrup

i see . so an an equation i need to finde the vales of x in this case!!! right

49. koli123able

Thus, the Solution Set is {25,25}

50. koli123able

right

51. koli123able

bye

52. koli123able

53. koli123able

send me a friend request http://www.facebook.com/koli123able/

54. koli123able

lets be friends

55. hal_stirrup

thanks. no i dont really use face book that much. but i will send you request.

56. koli123able

ok

57. hal_stirrup

cool