## anonymous one year ago Solve 3x2 + 6x = 8. 1 plus or minus 2 square root 33 the quantity of negative 3 plus or minus I square root 15 all over 3 the quantity of negative 3 plus or minus square root 33 all over 3 1 plus or minus 2 i square root 15

1. sepeario

Okay are these 5 different questions? It's really unclear.

2. sepeario

For the first bit to solve 3x^2 + 6x = 8, have you heard of completing the square?

3. anonymous

no the bottom ones are the answer choices

4. sepeario

Oh right. So have you heard of completing the square?

5. anonymous

no :/

6. sepeario

It's a way to solve the trinomial like you have above. I'll show you the steps. $3x^2+6x=8$ The first step is to move the constant (8) on the other side but that is already done. What you have to do now is to take half the coefficient of x and add it to both sides. Can you do that?

7. anonymous

idk how.... man i must sound dumb as hell XD

8. anonymous

@Sepeario

9. sepeario

Nah this is actually pretty hard.. but very useful when you learn it. In the term 6x, what is the coefficient of x (the number before x essentially).

10. anonymous

3?

11. campbell_st

the easiest thing to do is rewrite the equation as $3x^2 + 6x - 8 = 0$ then use the general quadratic formula for a quadratic $ax^2 + bx - c = 0$ the formula is $x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$ your question has a = 3, b - 6 and c = -8 substitute the values and calculate the answers

12. campbell_st

oops b = 6 a typo in the response above.

13. sepeario

or you could do that.. I like completing the square. if you learn it it's much quicker than substituting values into the formula.

14. anonymous

lol you still at this?

15. anonymous

must be like a homework marathon

16. anonymous

lol 51 questions XD @satellite73

17. anonymous

i hope this is like 47 at least

18. sepeario

what topic is this on?

19. anonymous

do what @campbell_st said use $x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$ with $a=3,b=6,c=-8$ that is all compute carefully

20. sepeario

probably quadratics and polynomials and stuff like that

21. anonymous

i am i got $-6\pm \sqrt{132}\6$

22. anonymous

want me to check it?

23. anonymous

idk i just want the answer XD

24. anonymous

im tired of algebra. its been 3 hours and im still on the same freaking thing!

25. anonymous

that is the answer, before you "simplify it" it is probably not one of your answer choices

26. anonymous

is one of them $\frac{-3\pm\sqrt{33}}{3}$?

27. anonymous

yes XD

28. anonymous

then pick that one

29. anonymous

how many more?

30. anonymous

What is the simplified form of 3 over 2x minus 5 + 21 over 8 x squared minus 14x minus 15 ? 6 times the quantity 2 x plus 5 end quantity over the quantity 2x minus 5 end quantity times 4 x plus 3 6 times the quantity x plus 1 end quantity over the quantity 2x minus 5 end quantity times 4 x plus 3 6 time the quantity x plus 1 end quantity over the quantity 2x minus 5 end quantity times 4 x plus 3 6 times the quantity x plus 1 end quantity over the quantity 2x plus 5 end quantity times 4 x plus 3

31. anonymous

yikes

32. anonymous

those are just answer choices XD

33. anonymous

and i think that it is 6 times the quantity x plus 1 end quantity over the quantity 2x minus 5 end quantity times 4 x plus 3

34. anonymous

$\frac{3}{2x-5}+\frac{21}{8x^2-14x-15}$ like that?

35. anonymous

yes

36. anonymous

i can't read your answer really i know the denominator is correct $(2x-5)(4x+3)$

37. anonymous

6(x+1)/(2x-5)(4x+3)

38. anonymous

What is the simplified form of the quantity 15 x y squared over x squared minus 5x plus 6 all over the quantity 5 x squared y over 2x squared minus 7x plus 3 ? 3y times the quantity 2x plus 1 over x times the quantity x plus 2 x times the quantity x plus 2 over 3y times the quantity 2x plus 1 x times the quantity x minus 2 over 3y times the quantity 2x minus 1 3y times the quantity 2x minus 1 over x times the quantity x minus 2

39. anonymous

yikes

40. anonymous

hard to read again let me try

41. anonymous

XDDD

42. anonymous

$\frac{15xy^2}{x^2-5x+6}$?

43. anonymous

i need a screenshot maybe

44. anonymous

idk how to do that

45. anonymous

hit "print screen" on your keyboard, then attach it

46. anonymous

47. anonymous

it's not working...

48. anonymous

ok give me a second was any part of what i wrote correct?

49. anonymous

i bet it was a compound fraction which amounts to $\frac{15xy^2}{x^2-5x+6}\times \frac{2x^2-7x+3}{5x^2y}$

50. anonymous

|dw:1438565010844:dw|

51. anonymous

yeah what i wrote

52. anonymous

"invert and multiply" and get $\frac{15xy^2}{x^2-5x+6}\times \frac{2x^2-7x+3}{5x^2y}$ as a first step

53. anonymous

then cancel some stuff, not much goes though

54. anonymous

i don't understand

55. anonymous

when you divide by a fraction you "invert and multiply" just like with numbers

56. anonymous

all i did was flip the denominator of the expression you wrote then you can cancel a bit

57. anonymous

oh gotcha

58. anonymous

$\frac{3y(2x^2-7x+3)}{x(x^2-5x+6)}$

59. anonymous

nothing else cancels, so either that is the final answer or there is a typo

60. anonymous

that cant be

61. anonymous

ok i need something better sure you cannot take a screen shot?

62. anonymous

3y times the quantity 2x plus 1 over x times the quantity x plus 2 this is the closest thing to that

63. sepeario

are you on a mac or windows?

64. anonymous

windows

65. sepeario

is there a prt scr button?

66. anonymous

yes and i pressed it multiple times and it doesnt wrk

67. anonymous

ok i think i got it

68. anonymous

Bob and Susie wash cars for extra money over the summer. Bob's income is determined by f(x) = 6x + 13, where x is the number of hours. Susie's income is g(x) = 4x + 18. If Bob and Susie were to combine their efforts, their income would be h(x) = f(x) + g(x). Assume Bob works 3 hours. Create the function h(x) and indicate if Bob will make more money working alone or by teaming with Susie. A h(x) = 2x + 5, work alone B h(x) = 2x + 5, team with Susie C h(x) = 10x + 31, team with Susie D h(x) = 10x + 31, work alone

69. anonymous

lol i have seen this exact silly question before

70. anonymous

$h(x)=f(x)+g(x)=6x+13+4x+18$

71. anonymous

combine like terms and get $h(x)=10x+31$

72. anonymous

yea but would that be team with susie or work alone?

73. anonymous

hmm depends

74. anonymous

$f(3)=6\times 3+13=31$

75. anonymous

$h(3)=10\times 3+31=61$

76. anonymous

if he has to split the money with susie he is better off working alone

77. anonymous

lol okaiis

78. anonymous

i can tell the end is in sight

79. anonymous

A function is created to represent the costs of living per person in the family. What restrictions would be made to the domain?

80. anonymous

i guess it would have to be greater than or equal to zero

81. anonymous

A.The domain would only include integers. B.The domain would only include positive integers. C.The domain would only include positive numbers. D.The domain would include all real numbers.

82. anonymous

i am going to make a guess, because none of this really makes too much sense

83. anonymous

make it a good guess XD

84. anonymous

A and B are clearly wrong, since it could be decimals (it is money after all)

85. anonymous

i would go with C

86. anonymous

can't imagine the cost of living is negative

87. anonymous

i only make good guesses they are, however, just guesses

88. anonymous

To which graph does the point (−1, 3) belong? A.y ≥ 2x + 6 B.y ≥ 3x − 1 C.y ≥ −x + 4 D.y ≥ −2x + 5

89. anonymous

idk lets try the first one is $3\geq 2(-1)+6$?

90. anonymous

nope you would have $3\geq 4$which is false

91. anonymous

this makes no sense

92. anonymous

sure it does

93. anonymous

$$(-1,3)$$ is your $$(x,y)$$

94. anonymous

so to see if it satisfies $y\geq 3x-1$ put $$x=-1$$ and $$y=3$$ and see if the inequality is right or wrong

95. anonymous

thsts what i thought

96. anonymous

you get $3\geq 3(-1)-1$ or $3\geq -4$ which is definitely true

97. anonymous

so at least that one is right can there be more than one answer?

98. anonymous

im done :D Let's see what i get!

99. anonymous

100. anonymous

71%!!!!! :D

101. anonymous

now get away from the computer, stop doing math

102. anonymous

is that all?

103. anonymous

lol i might do one more XD

104. anonymous

should have got at least 95 with all the brilliant help you have been getting

105. anonymous

go have a beer, do it tomorrow if you are too young to have a beer, have a snack

106. anonymous

Simplify completely quantity x squared plus 12 x plus 35 all over 3 x plus 15.

107. anonymous

quantity of x squared plus 21 over 3 quantity of x squared plus 11 over 3 quantity x plus 7 over 3 quantity of x plus 5 over 3

108. anonymous

just one more CX

109. anonymous

one more assignment i mean CX

110. anonymous

one more question for me

111. anonymous

awh man CX you're the only one responding CX

112. anonymous

$\frac{x^2+12x+35}{3x+15}=\frac{(x+5)(x+7)}{3(x+5)}$ $=\frac{x+7}{3}$

113. anonymous

got it cx

114. anonymous

take a break for heaven's sake i went out, had dinner, watched an episode of columbo, and you were still here

115. sepeario

^^ that rhymed

116. pooja195

117. anonymous

cx how is this sad CX

118. pooja195

It just is.