t suqare

• yiha093

  1 Oct 07, 22:32

  2
  t =-5t
  
  how solve?
  eh, plz explain too
• yongyong

  1 Oct 07, 22:37

  Originally posted by yiha093:

  2
  t =-5t
  
  how solve?
  eh, plz explain too

  t^2 + 5t = 0
  t = -5
• eagle

  1 Oct 07, 22:37

  t^2 + 5t = 0
  
  t(t+5) = 0
  
  t = 0 or t = -5
  
  Do not cancel the t away or you will lose a solution
  
  Regards,
  Eagle
• yiha093

  1 Oct 07, 22:46

  Originally posted by eagle:

  t^2 + 5t = 0
  
  t(t+5) = 0
  
  t = 0 or t = -5
  
  Do not cancel the t away or you will lose a solution
  
  Regards,
  Eagle

  do explain the red part
  how u reach that?
• wishboy

  1 Oct 07, 23:08

  Originally posted by yiha093:

  do explain the red part
  how u reach that?

  factorise out the t in the equation
  
  t² + 5t = 0
  
  t² = t * t
  5t = 5 * t
  
  * = multiply
  
  both got t so can "take it out" which means factorise out the t
  
  so...
  t² + 5t = 0
  t * (t + 5) = 0
  therefore,
  t = 0 or t + 5 = 0
  t = 0 or -5
• yiha093

  1 Oct 07, 23:26

  Originally posted by wishboy:

  factorise out the t in the equation
  
  t² + 5t = 0
  
  t² = t * t
  5t = 5 * t
  
  * = multiply
  
  both got t so can "take it out" which means factorise out the t
  
  so...
  t² + 5t = 0
  t * (t + 5) = 0
  therefore,
  t = 0 or t + 5 = 0
  t = 0 or -5

  okie
  
  next question
  
  i have a rectangle
  3x-y
  3y+4 |----------------- |
  | | 2x-3
  |------------------|
  2x+y
  
  based on wad i c
  3x-y=2x+y
  2x-3=3y+4
  (stuck le)
  Find X and Y
  ?? any1 noes?
  
• yuko-ogura

  1 Oct 07, 23:30

  Originally posted by yiha093:

  okie
  
  next question
  
  i have a rectangle
  3x-y
  3y+4 |----------------- |
  | | 2x-3
  |------------------|
  2x+y
  
  based on wad i c
  3x-y=2x+y
  2x-3=3y+4
  (stuck le)
  Find X and Y
  ?? any1 noes?
  

  3x-y=2x+y
  Let x=2y---------------(1)
  and (2): 2x-3=3y+4
  
  Sub (1) into (2): 2x-3=3y+4
  2(2y)-3=3y+4
  4y-3y=7
  
  thus y=7 and x=14
• ^tamago^

  1 Oct 07, 23:32

  Originally posted by yiha093:

  okie
  
  next question
  
  i have a rectangle
  3x-y
  |----------------- |
  3y+4 | | 2x-3
  |------------------|
  2x+y
  
  based on wad i c
  3x-y=2x+y
  2x-3=3y+4
  (stuck le)
  Find X and Y
  ?? any1 noes?
  

  3x-y=2x+y ==> x=2y ---(1)
  2x-3=3y+4 ==> 3y-2x+7=0 ---(2)
  
  sub (1) into (2): y=7, x=14
  
• ^tamago^

  1 Oct 07, 23:33

  
• gLc

  1 Oct 07, 23:35

  im not sure how to do. But here goes.
  
  Since..
  
  3x-y=2x+y
  2x-3=3y+4
  
  Thus--> 2x = 3x-2y
  -x=-2y
  x=2y
  
  2x=3y+4+3
  2x=3y+7
  
  2(2y)=3y+7
  4y=3y+7
  
  4y-3y=7
  
  So, Y = 7.
  
  3x-(7)=2x+7
  3x-2x=7+7
  
  x=14
  
  So Y = 7, X = 14. I think..
• yiha093

  1 Oct 07, 23:40

  Originally posted by gLc:

  im not sure how to do. But here goes.
  
  Since..
  
  3x-y=2x+y
  2x-3=3y+4
  
  Thus--> 2x = 3x-2y
  -x=-2y
  x=2y
  2x=3y+4+3
  2x=3y+7
  
  2(2y)=3y+7
  4y=3y+7
  
  4y-3y=7
  
  So, Y = 7.
  
  3x-(7)=2x+7
  3x-2x=7+7
  
  x=14
  
  So Y = 7, X = 14. I think..

  thx for ur rreplies
  howeever
  still dun understand sum parts
  how get 2x=3x-2y?
• yiha093

  1 Oct 07, 23:41

  Originally posted by ^tamago^:

  

  txhthx
• ^tamago^

  1 Oct 07, 23:43

  Originally posted by yiha093:

  thx for ur rreplies
  howeever
  still dun understand sum parts
  how get 2x=3x-2y?

  Originally posted by gLc:
  im not sure how to do. But here goes.
  
  Since..
  
  3x-y=2x+y
  2x-3=3y+4
  
  Thus--> 2x = 3x-2y
  -x=-2y
  x=2y
  
  ....

• yuko-ogura

  1 Oct 07, 23:46

  3x-y=2x+y
  3x-2y=2x lor..
  
  hmm..i hope u noe how it works..cux if u dun...
• yiha093

  2 Oct 07, 17:11

  ok
  i was juz wondering y no have = ?( whole number)
  now noe k lee k thx xd