## anonymous one year ago Four expressions are shown below: 21x + 6 3(7x + 2) 18x + 9 3(6x + 3) Which two expressions are equivalent to 3(6x + 2 + x)? A and D C and D A and B B and C

1. anonymous

i believe one of them is C

2. Nnesha

3(6x + 2 + x) combine like terms

3. Nnesha

C is 18x+9 what is common factor ?

4. anonymous

I don't think it is C

5. anonymous

common factor 6?

6. Nnesha

GREATEST common factor.

7. Nnesha

18 and 9 are divisible by 6,3, and ?

8. anonymous

9

9. Nnesha

yes right so take out 9 (????) what would goe in the parentheses ?

10. Nnesha

when you take out 9 from 18x what will u have left ?

11. anonymous

um 6?

12. Nnesha

in other words you have to divide both terms by common factor |dw:1438796637464:dw|

13. Nnesha

18x/9= ? 9/9= ?

14. anonymous

9 and 1

15. Nnesha

18x divide by 9 = 9 ?

16. anonymous

i really don't know..

17. anonymous

oh 2

18. anonymous

sorry its 2

19. Nnesha

2x

20. anonymous

yes

21. Nnesha

|dw:1438796981240:dw| now tell me is it equivalent to 3(6x + 2 + x)?

22. Nnesha

$\huge\rm 3(\color{ReD}{6x}+2+\color{red}{x})$combine like terms

23. anonymous

Yes its equivalent

24. anonymous

nvm its not

25. Nnesha

yes right

26. Nnesha

$$\color{blue}{\text{Originally Posted by}}$$ @Nnesha $\huge\rm 3(\color{ReD}{6x}+2+\color{red}{x})$combine like terms $$\color{blue}{\text{End of Quote}}$$ combine them let mek now what you get

27. anonymous

i thought its equivalent because 6x3=18 and 6+3=9

28. Nnesha

you don't have to combine 6+3

29. Nnesha

distribute parentheses by outside term to check ur answer

30. Nnesha

first of all 3(6x+2+x) here what are like terms in the parentheses ? combine them you will get one of answer

31. anonymous

3 is a like term

32. Nnesha

no i said in the parenthess

33. anonymous

6x

34. Nnesha

and ?

35. Nnesha

$$\color{blue}{\text{Originally Posted by}}$$ @Nnesha $$\color{blue}{\text{Originally Posted by}}$$ @Nnesha $\huge\rm 3(\color{ReD}{6x}+2+\color{red}{x})$combine like terms $$\color{blue}{\text{End of Quote}}$$ look at that i changed the color of both like terms

36. anonymous

x

37. Nnesha

yes right so combine them 6x+1x=?

38. anonymous

7x

39. Nnesha

yes right so 3(6x+2+x) is 3(7x+2)

40. Nnesha

now look at the answer choices which one is equivlent to 3(7x+2)

41. anonymous

C

42. Nnesha

alright distribute parenthesses by 3 3(7x+2) = ??? is it equivalent to 18x+9 ?

43. anonymous

i know now

44. anonymous

A and b because they both = 27

45. Nnesha

distributive property a(b+c) =a times b + a times c =ab+ac

46. Nnesha

they both 27 ?

47. Nnesha

you CAN"T combine 21x+6 they are not LIKE terms

48. Nnesha

21x is not same as 6 ^^x variable ^without any variable

49. anonymous

ok sorry i messed up nvm scratch that

50. Nnesha

3(7x+2) distribute |dw:1438798106649:dw|

51. Nnesha

52. anonymous

3(7x+2) = ??? is it equivalent to 18x+9 ? Yes there equivalent

53. Nnesha

54. anonymous

ok

55. anonymous

7x+2= 9 3x9=27 18x+9=27 they both equal 27

56. anonymous

am i wrong?

57. Nnesha

first of how did you get 9 how 7x+2 equal to 9 ?

58. Nnesha

2nd i just told you can't combine a number with variable with number without variable like 18x+9=27 18 have x variable but 9 doesn't so they are not like terms

59. Nnesha

$\huge\rm 3(6x+2+x)=3(7x+2)$ so which answer choices is same as 3(7x+2) ?

60. anonymous

ok then clearly i am confused on what im doing

61. anonymous

21x + 6 it has a variable so you can combine it

62. Nnesha

do you mean combine 21x and 6 ?

63. anonymous

no i mean 3(7x+2) and 21x + 6 they both have a variable so you can combine them

64. Nnesha

you need two expression that are equivalent to 3(6x+2+x) (same as 3(7x+2) now you can see one of answer choice is 3(7x+2) so 3(7x+2) is equivalent to 3(7x+2)

65. Nnesha

they both are different equation you don't have to combine them

66. Nnesha

|dw:1438798858408:dw| 3(7x+2) is same as ??? distribute 7x and 2 by 3

67. Nnesha

$\huge\rm \color{ReD}{3}(7x+2)=\color{reD}{3} \times 7x + \color{ReD}{3} \times 2$ = ??

68. anonymous

before i do this 7x is just like saying 3x7 right or no?

69. Nnesha

yes right (3 times 7)x

70. anonymous

ok then i got 27

71. Nnesha

3 times 7x = 27x ?

72. anonymous

ok im confused on the x isnt it just 3 x 7 which is 21?

73. Nnesha

here are some example of like terms 4x+3x=7x 4y+4y= 8y 4x+3 isn't equal to 7x no! you can't combine 4x with 3 they are not like terms

74. Nnesha

4x+3 is just 4x+3

75. Nnesha

yes 3 times 7x =21x

76. Nnesha

3 times 2 = 6 right ? |dw:1438799303607:dw| so 3(7x+2) is equivalent to 21x+6

77. anonymous

yes

78. anonymous

79. Nnesha

how ??

80. anonymous

ohhh

81. Nnesha

21x+6 is just 21x+6 you CAN'T combine them they are NOT LIKE terms

82. Nnesha
83. anonymous

i see im not suppose to do anything after that i was doing 21x+6=27x i thought i had to finish the problem...

84. Nnesha

no you can't combine 21x+6 its just like making milkshake of mangoes and onion

85. anonymous

i see *lightbulb

86. anonymous

i wasn't thinking in that way

87. Nnesha

so can you combine 4z+5y (example ) ??

88. anonymous

no because there not like terms

89. Nnesha

true good!