## Thursday, 19 January 2012

### Algebra Change of Subject 2(review)

Pair work (follow-up from previous Task Algebra Change of Subject 2)

Based on the activity in task 1, students have submitted the following responses (refer Table 1).

Identify at least 2 points for consideration for 'Change of Subject'. Example Arithmetic error (wrong associative law applied)
You may discuss with a partner in class.

Submit this as a comment.

reference:
Worksheet 5, ACE learning.

Question Posted by Teacher

Table 1: Answer Posted by Students

1. Student D:
Error: Did not change the right hand side of the equation from + to - when he changed the left hand side from - to + and did not divide 2z by p.

2. Tan Yu Tao, Jonathan Tan
Multiplication and division error
Arithmetic error

3. Student D:
He/She did not divide the 2z by the p and also did not change the addition and subtraction symbols properly.

4. Student A,B,L,Q,C,E,H,I,M,R = Did not inverse the operation from + to -
Student
Student F = Correct
Student D = Forgot to divide P
Student J = The subject should only be on the left

By Sylvia and Esther

5. This comment has been removed by the author.

6. Student A,B,L,Q,C,E,H,I,M,R = Did not inverse the operation from + to -
Student
Student F = Correct
Student D = Forgot to divide P
Student J = The subject should only be on the left

By Sylvia and Esther

7. Student "I" has left the "ans)" there and did not find the solution for z-2z which should be -z.

8. Student C:
Did not change the right hand side of the equation from multiplication to division. So in stead of 2z/p it became 2zp.

9. Student N- The 2z should be a fraction with the p instead, 2z the numerator while p the denominator .

10. Student C did not divide the equation by p and he did not change the signs for both sides of the equation.

11. Student C did not make the 2z divide by p

12. Student N - The 2z should actually be the fraction with p.

13. student D did not make the 2z divided by p, but multiplied it instead

14. Only Student F got it correct, Student D is close but he/she did not divide p. Student J is correct except the fact that the subject is on the right side. The rest got the question wrong because they did not inverse the answer.

15. Student G :

Did not change + to - when changing sides for 2z

pz is supposed to be a + not a -

16. Student C:
Arithmetic error, when he transferred it over the equals sign, he forgot to change it to a divide sign.
Distributive error, did not distribute the - to the z

17. Student P has put way too many spaces. the Majority of the mistakes made by students is due to wrong conversions. They forgot about the - and + sometimes leading it to be confusing.

18. Student G - Arithmetic error and did not bracket the numerator, confusion if [2z-(zp/p)] OR [(2z-zp)/p]

19. Student D:
Did not divide the p

20. Student N
It is supposed to be 2Z as the numerator of the fraction where P is the denominator and not the other way around with Z being the numerator.