## Faman39 Group Title Please help me to understand and solve these! one year ago one year ago

1. Faman39

2. Faman39

@mathmate can you able to help me with this?

3. mathmate

DId you work out the solutions to each of the inequalities?

4. Faman39

I didnt understand completely those problem, thats y

5. mathmate

Solve them as equations, and since they are <, so you need any answer that is smaller the equality.

6. Faman39

I cant really get it how to do it, but i did somehow, where i got half n half write. I need to understand whole n how to find the rite answer

7. mathmate

The questions are all inequalities. Say you solve the first one as an equality: -2(1+z)+5z+5<11 -2-2z+4z+5<11 2z<11-3=8, or z<4 So any of the answers will fit for #1. Now proceed with #2, #3, #4 and try to move a,b,c,d around so that ALL the inequalities are satisfied.

8. Faman39

cqn you wait, cuz i m gonna show you those.

9. Faman39

First one will fit on which one, would it be 2

10. mathmate

Because they are not equations, but inequalities, you are better of doing all 4 of them before fitting anything. For example, all the answers a,b,c,d will fit in the first. So you don't know which one to choose until you have all 4 inequalities solved.

11. mathmate

Note: inequalities have multiple answers.

12. Faman39

So but i want to how will i get this answer matching correct answer

13. Faman39

Of all of them

14. mathmate

Let say if you have a set of answers 1,3,5,7 and solutions to equations which are x<2,x<6,x<8,x<4 Then your choice would be to fit 1<2, 5<6, 7<8,3<4, or else you would have one left over such as: 1<2,3<6,5<8, but 7>4 will not work. That's why you need to work out all four before you can match.

15. Faman39

Ok so, -2 (1 + z) +4z +5 <11 -2 + -2z + 4z + 5 <11 -2 + 2z + 5<11 so does it mean 2 will match or no?

16. mathmate

You have to solve it completely, -2+2z+5<11 2z+3<11 2z<8 z<4 Now you still have to solve the other three before you can start matching.

17. Faman39

that 2 match with this one right?

18. mathmate

All four answers will match with this one. If you want to take a chance, choose the highest number that will match. But I suggest you work out ALL 4 inequalities, then match. That will be much more sure.

19. mathmate

all four will match, because 3<4 -3<4 2<4 0<4 . That is why I suggest you work out all four inequalities before matching.

20. Faman39

All does not matched up, thats y, i m asking, how will i figure out all this

21. mathmate

If you want, you can pick 2<4. If you choose now, the rest may or may not work.

22. mathmate

1. Solve all FOUR inequalities, so you have 4 inequalities in hand, such as z<4 z< ? z< ? z< ? 2. Match the 4 given answers so that EVERY inequality works.

23. Faman39

Second will be -3, am i right?

24. mathmate

I'm afraid not. You have a problem with the sign.

25. mathmate

...unless you mean -z>-3

26. Faman39

I was saying according that table which i showed

27. Faman39

So it suppose to match up with b -3

28. Faman39

right?

29. mathmate

Inequalities are not equations. Solutions must remain inequalities. So the second one must be given in the form z<-3, or z>3, or z<3. -3 would not be the solution to an inequality. Can you show your work?

30. Faman39

ok

31. Faman39

3z - 5z +10 - 8 <6

32. mathmate

3z - 5z +10 - 8 does not look right. Can you check?

33. Faman39

2z + 10 - 8 <6 so if this be 2, then other was not 2

34. Faman39

I cant really know how to do these all

35. Faman39

Problems seems really confusing to me

36. mathmate

3z - 5z +10 - 8 <6 is inorrect. it should be +5z and -10. How did you get the signs reversed?

37. mathmate

Or written in full 3z+5z-10-8<6

38. Faman39

so your saying it would match up with 3, right?

39. Faman39

Thats how we find the 3

40. mathmate

You are going to far with matching. You need to solve ALL 4 inequalities before you can match. the answer to the second is then....?

41. mathmate

I mean the $$solution$$ to the second inequality is then....?

42. Faman39

I dont get at all how to last four, thats y i put their answer by guess, i m sure those last two were wrong but there is two matching which i gave, it was correct

43. mathmate

If you don't need all four correct, that's ok. Go ahead and do it your way. I have no problem with that. Good luck with your guesses. :)

44. mathmate

In mathematics, you are allowed to guess, but you also need a way to check your answer. If you cannot do both, then, sorry, guessing is not the right way.

45. Faman39

Thank you but all i wanted to know how to solve these, i havent done all by guess just two one which mite, but um not sure abt how to solve it to find exact answer to match. I just want to be clear abt all this

46. Faman39

I m not getting to find all of it exact answer

47. mathmate

I repeat: 1. Solve ALL four inequalities in the form z<4 z<3 z< ? z< / 2. THEN match the inequalities with the 4 given answers to make sure ALL inequalities are satisfied. I am still waiting for the solution to the second inequality after I have done the first one. If you have problems solving inequalities, that's where you need to work on.

48. Faman39

3z - 10 + 5z - 8 <6 3z + 5z + 10 - 8 <6 8z + 2<6

49. Faman39

8z + 2 - 2 <6 8z <6

50. Faman39

it will be a 0?

51. Faman39

No

52. Faman39

53. Faman39

I dont understand how to solve all this

54. Faman39

@CalebBeavers help me please

55. Faman39

@phi

56. Faman39

Thank you so much for helping tolerating pain like me, i m sorry so for trouble. I really appreciate your help @mathmate, thanks alot! :)

57. Faman39

This one @experimentX

58. experimentX

first of all simplify the left side. Can you simplify $-2(1+z) + 4z + 5$

59. Faman39

-2z + -2z + 4z +5 4z +4z +5 8z +5

60. Faman39

isnt it?

61. experimentX

nope!!

62. experimentX

$-2(1+z) = (-2) \times 1 + (-2) \times z = ?$

63. Faman39

-2 +2z = -2 (-2) X z = -2 + 2z = -4 X z I m stuck :( sorry

64. Faman39

-2

65. experimentX

$-2 \times z = ?$

66. Faman39

-2z

67. experimentX

-2 + (-2z)= ?

68. Faman39

4z?

69. experimentX

no ... you cannot add like that.

70. experimentX

|dw:1358353383731:dw|

71. experimentX

do you know how to take common?

72. Faman39

3x + 3x

73. experimentX

|dw:1358353592998:dw|

74. Faman39

5x

75. experimentX

yes!!

76. experimentX

1$+ 2$ = 3$1$ + 2 pound = 3\$ ------------------ which of above is correct?

77. Faman39

3?

78. Faman39

both are same

79. experimentX

what is the name of your currency?

80. Faman39

pound

81. experimentX

okay .. is 1 dollar + 2 pound = 3 dollar ?

82. Faman39

no

83. experimentX

is that correct?

84. Faman39

no

85. experimentX

why not?

86. Faman39

Both are not similar

87. experimentX

yep!! -2 + (-2z) here think of z as dollar and ... ther is nothing after -2 ... think of it as there is pound.

88. Faman39

So what i did on all that problems, so how do i match because, its seems tricky

89. experimentX

also I think there is no minus there. your first problem is $2(1+z) + 4z+5 = ?$ Simplify this. thikn of $$4z + 5$$ as .. 4 dollar + 5 pound

90. Faman39

it cannot be added

91. Faman39

so the bracket one what we need to do

92. experimentX

at least you can make it a bit simpler.

93. Faman39

-2 + 2z +4z +5 - 2 + 6z +5

94. Faman39

?

95. experimentX

quite not correct. + ( - 2z) = ?

96. experimentX

no ... |dw:1358354499867:dw|

97. Faman39

-2z

98. Faman39

so 2 match up with this?

99. Faman39

I meant, first problem

100. experimentX

okay now simplify the first problem.

101. Faman39

-2z + 5 < 11

102. Faman39

-2z < 6

103. Faman39

z < 6/-2 z < -3

104. Faman39

it is match up with b

105. experimentX

No ... you didn't do it correctly.

106. Faman39

divide both side

107. Faman39

right?

108. Faman39

i forgot, just did one side directly

109. experimentX

woops!! sorry ... your first problem. $-2(1+z) + 4z+5 = -(2(1+z)) + 4z+5 = -(2\times 1 + 2 \times z) + 4z + 5 \\ = -(2 + 2z) + 4z+5 = -2 - 2z + 4z+5 = (-2z+4z) + (-2+5) = 2z + 3$

110. experimentX

do you understand the each step?

111. Faman39

but am i right with first one?

112. experimentX

did you get 2z+3?

113. Faman39

no i got -3

114. experimentX

2z+3 < 11 2z+3 - 3 < 11 - 3 2z . (1/2) < 8/2 = 4 http://www.wolframalpha.com/input/?i=-2%281%2Bz%29+%2B+4z%2B5+%3C%3D+11

115. experimentX

if you had done it correctly ... you should have got $z < 4$

116. Faman39

you are saying it match up 3

117. Faman39

right?

118. experimentX

yes copy these each step into your notebook and see if you understand each of these steps \begin{align*} -2(1+z) + 4z+5 &= -2(1+z) + 4z+5 \\ &= -2(1+z) + 4z+5 \\ &= -(2(1+z)) + 4z+5 \\ &= -(2\times 1 + 2 \times z) + 4z + 5 \\ &= -(2 + 2z) + 4z+5 \\ &= -2 - 2z + 4z+5 \\ &= (-2z+4z) + (-2+5) \\ &= 2z + 3 \end{align*}

119. Faman39

thank you :) it making sense now

120. Faman39

thank you so much

121. experimentX

also if you have any misunderstanding ... don't hesitate to ask.

122. Faman39

can you show me other 3, if your not busy or if i didnt eaten up your head, i know i m painful, i hardly understand everything in math

123. Faman39

thats really horrible

124. experimentX

first simplify do 2nd and 4 th problem

125. experimentX

i think you are capable to do it .. also show me step!!

126. Faman39

3z + 5z - 10 - 8 < 6?

127. experimentX

yes go on!!

128. Faman39

8z - 10 - 8 <6 8z - 2 <6 8z <6 +2 8z < 8 z < 0

129. experimentX

http://www.wolframalpha.com/input/?i=3z+%2B+5z+-+10+-+8+%3C+6 watch your second step again.

130. Faman39

Sorry so, 8z - 18 < 6 8z < 6 - 18 8z < 12 1.5? :(

131. experimentX

8z - 18 < 6 add +18 to both sides.

132. Faman39

8z < 24 <3

133. experimentX

yes correct!! do the 4th problem similarly ... also note the mistake you made Sorry so, 8z - 18 < 6 8z < 6 - 18 8z < 12 (is 6-18 = 12 ??) 1.5? :( Get calculator. or watch your step agai.

134. Faman39

In third one, how do i start?

135. experimentX

watch the example i gave you!!

136. Faman39

I m so sorry, i m such a error maker, pls forgive me for all this trouble

137. experimentX

in which level do you study?

138. Faman39

no actually im in online high school, where i m takin blended course

139. experimentX

really? you got terrible math!! these are very very basic simple rules

140. Faman39

yes, im ok with other but worse in math

141. experimentX

okay try 3

142. experimentX

what did you put on 2?

143. Faman39

Z + 5 - ( 1 + 6z) > -1

144. Faman39

z +5 - 1 + 6z > -1

145. experimentX

there you have problem!! -(1+6z) = -1 times .. what's inside

146. experimentX

|dw:1358357567000:dw|

147. Faman39

-1 + -6z

148. experimentX

what is + - 6z = ?

149. Faman39

- 6z

150. experimentX

yes ... now simplify it

151. Faman39

7z

152. experimentX

again, you are not getting the point. look at the big picture. look again from where you started and where you ended. and check for errors.

153. Faman39

ok sorry

154. Faman39

z + 5 - -1 + -6z <1

155. experimentX

it's necessary that you write the whole step on some nontebook.

156. experimentX

*notebook ... if you rely on memory then you will never learn. also it's necessary that you have to look at your previous step.

157. Faman39

ok sure, i will keep it mind. z + -6z + 5- + -1 5z + 6 < 1

158. Faman39

I know, something wrong in here again

159. Faman39

5z < 1 - 6 5z < 5 1

160. Faman39

<1

161. Faman39

am i wrong?

162. experimentX

try pluggin that expression on Wolfram Alpha

163. Faman39

I dont know how to do it

164. Faman39

:(

165. Faman39

166. experimentX

how do you do with this $a + 2b - (3a+b) = a + 2b - 3a -b = a-3a+2b-b = -2a +b$

167. Faman39

add by combining like term

168. experimentX

how did i get rid of -(3a+b) .. just do it like there.

169. Faman39

- 3a + b, we cant go more from this on it

170. experimentX

- 3a - b

171. experimentX

|dw:1358359171654:dw|

172. Faman39

so then your saying it will move to positive

173. Faman39

But i didnt understand how did operation + to - at middle

174. Faman39

Hows did you change and why?

175. experimentX

no ... |dw:1358359302646:dw|

176. Faman39

ok

177. experimentX

|dw:1358359471738:dw|

178. Faman39

not equal

179. Faman39

yes

180. Faman39

you multiplied - all on Bracket, thats y, everything -

181. experimentX

|dw:1358359803427:dw|

182. Faman39

- 3a + -2b

183. experimentX

tell me in terms of pounds and dollars .... how much should you give to me?

184. Faman39

3 dollar, 2 pounds

185. experimentX

isn't that equal to -3a-2b? what does this mean?

186. experimentX

|dw:1358360151961:dw|

187. experimentX

|dw:1358360292451:dw|

188. experimentX

|dw:1358360405299:dw||dw:1358360432011:dw|

189. Faman39

got it now :) thank you

190. Faman39

thats y it was - 1, right

191. experimentX

Honestly, I feel like you are trolling with me!! right ... do the third number now and show it to me.

192. Faman39

I m extremely sorry for taking your time n making you crazy like this

193. Faman39

:( i m so sorry for everything

194. Faman39

- 7z - 19 + 19 < 5 +19 -7z + < 24 got long decimal number

195. experimentX

you copied the wrong question. - 7z - 19 + 19 < -5 +19

196. Faman39

so first one was right ?

197. Faman39

which i showed you b4

198. experimentX

no you had +7z ...

199. Faman39

-8z - 19 + z > - 5

200. Faman39

so -7z + 19 < 5 - 7z + 19 - 19 < 5-19 -7z < 14 z < -2

201. experimentX

well ... done!! gotta go ... i strongly suggest that you get a pencil and notebook and practice few similar problems.

202. Faman39

Thank you so much! im sorry again for trouble :(

203. experimentX

I am not in trouble ,,, you might be in math test!! so pratice well!!

204. Faman39

yes, i was trying understand these so that i dont make mistake again like this

205. Faman39

Last one match up with 2, right, just to be confirmed

206. Faman39

i m extremely apologize for giving you trouble @experimentX. thank you so much for helping me alot! you really saved me explaining all of it. I m really very sorry horribly troubling you

207. Faman39

You are really amazing, thank you so much for make me understand abt all of it without being tired. your truly great, thanks alot @experimentX