Thursday 19 January 2012

Algebra Change of Subject 2(review)

y=x-(2x-1)(1/T) 1
y=[x(T-2)+1]/T 1
y=T+3x-1 1
y=T(2x-1)-x 1
y=1+T-x 1
y=-[T(2x-1)/x] 1
y=(Tx+1-2x)/T 1
y=(-2x+1/T)+x 1
y=(-2x+1+Tx)/T 1
y = (2x=1)*(x-T) 1
Tx/x=1/(-y)
-Tx/x=y
y=-Tx/x 1
Tx-Ty=2x-1
-Ty=2x-1-Tx
Ty=Tx+1-2x
y=(Tx+1-2x)/T 1
T=(((2x-1))/((x-y)))
(x-y)(T)=(2x-1)
xT-yT=2x-1
x-y=((2x-1)/(T))
y=-(x((2x-1)/(T))) 1
T=(2x-1)/(x-y)
T(2x-1)=x-y
2xT-T =x-y
2xT-T-x=-y
-x=y 1
T(x-y)=2x-1 1
(x-y)T=(2x-1)
(x-y)=(2x-1)/T
-y=[(2x-1)/T]-x
y=[(1+2x)/-T]+x 1
(2x-1)/T - x = y 1

18 comments:

  1. Error: Tx-Ty=2x-1
    Explain: Does not understand the change of subject clearly. y is not the subject in this equation.


    Correct answer: y=(-2x+1+Tx)/T

    ReplyDelete
  2. This comment has been removed by the author.

    ReplyDelete
  3. Error: -Tx/x=y
    Explanation: Did not simplify 'x' properly. 'x' should have been implied further. Also, the negative should be passed to the 'y' instead of the subject, 'T'

    Correct Answer: T = -y

    ReplyDelete
  4. Error 1
    Tx/x=1/(-y)

    Explanation: 'y' is not the subject in the formula. Does not know how to change the subject of the question correctly. The formula is not complete yet

    ReplyDelete
  5. error: (x-y)=(2x-1)/T
    Explanation: Does not understand the change of subject, y should have been the subject and not (x-y)=(2x-1)/T.

    Correct answer: y=(-2+1+Tx)/T

    ReplyDelete
  6. Error: Tx-Ty=2x-1
    Explanation: y is not the subject of this equation, thus it is not simplified to the simplest.
    Correct answer: y=(-2+1+Tx)/T.

    ReplyDelete
  7. Error 1
    -Tx/x=y

    explain: conceptual error, misunderstanding of question, the numbers were not considered
    correct answer y = (-2x+1+Tx)/T

    ReplyDelete
  8. y = (2x=1)*(x-T) 1

    y=(2x=1) <---- that just doesn't make senses, i think the student pressed the wrong key and did not double check his/her answer

    correct answer is y=(-2x+1+tx)/t

    ReplyDelete
  9. Error:-y=[(2x-1)/T]-x

    Explanation:The student forget to change the negative 'y' into positive 'y' .

    Correct answer: y=(Tx+1-2x)/t)

    ReplyDelete
  10. error:-y=[(2x-1)/T]-x
    Explanation: This student changed the subject from y to -y which is wrong. He or she might have made a mistake when doing the sum and therefore get the wrong equation or might have seen the subject wrongly

    ReplyDelete
  11. Error:
    Tx-Ty=2x-1

    Explain: Should continue to factorize further.

    Correct answer: y=(-2+1+Tx)/T
    ReplyDelete

    ReplyDelete
  12. Error: [ Tx-Ty=2x-1 ]

    Explanation: Has not understood the change of subject clearly. y is not portrayed as the subject of this equation.

    Correct answer: [ y = (-2x+1+Tx)/T ]

    ReplyDelete
  13. Error:-Ty=2x-1-Tx
    Explain:-ty should not be the subject of the formula, but y instead.Some steps have been missed out.

    Correct answer:y=(-2x+1+tx)/t

    ReplyDelete
  14. xT-yT=2x-1

    Explanation: Y isn't the subject of this equation.

    Ans: y = (-2x+1+Tx)/T

    ReplyDelete
  15. Error 1:
    y=(-2x+1+Tx)/T 1
    y = (2x=1)*(x-T) 1

    More steps than needed, cannot be factorised this way.

    Error 2:
    -Ty=2x-1-Tx
    Ty=Tx+1-2x

    Minus sign(-) cannot be only applied to one number, but to the whole side of the equation.

    ReplyDelete
  16. error:-y=[(2x-1)/T]-x
    Explanation: This student changed the subject from y to -y which is wrong. He or she might have made a mistake when doing the sum and therefore get the wrong equation or might have seen the subject wrongly

    ReplyDelete
  17. Error:Tx-Ty=2x-1
    explanation: Y is supposed to be the subject hence it should be y= -(2x+1-Tx)/T

    ReplyDelete
  18. Error: Tx-Ty=2x-1
    Explanation: y is supposed to be the subject, not -y, the student still has to multiply both sides of the equation to get y=1+Tx-2x

    ReplyDelete