Answers to Chapter 6 Revision Worksheet 1

1) x = -3 or x = 2

2) x = -1/6 or x = 2/3

3) r = 1/2

4) y = 0 or y = 4

5) not taught yet

6) p = -4 or p = 5

7) x = 0 or x = 1.5

8) x = -9 or x = 9

9) x = 1/14 or x = -3

10) m = 4/3 [pls change it to mixed fractions] or m = -1/2

11) t = 0 or t = -2 or t = 2

12) x = 3/5 or x = -3

13) h = -6 or h = 4

14) p = 0 or p = 6

15) x = 2 or x = 5

16) h = 0 or h = 2

17) x = -2/3 or x = 1/2

18) x = -6 or x = 6

19) x = -2/3 or x = 6

20) x = 9 or x = -7

21) x = -1/2 or x = 3

22) x = -1.5

23) x = -3 or x = 1/2

24) x = 2 or x = 5

25) not taught yet

26) p = -2 or p = 2

27) p = 0 or p = -2/15

28) x = -2/5 or x = 4

29) x = 1/3 or x = -4

30) u = -2 or u = 2

31) x = 2 or x = -1

32) x = 5/3 [please change to mixed fractions] or x = -1/2

Hope you have got most of the questions right. Note that the test will be of a higher standard so i would suggest you to redo Worksheet 1 - 3 again as a form of revision!

Note that the Mode 22 function of the calculator is strictly meant for checking purposes... you still have to master the skill of solving quadratic equations.

Here's some common mistakes made...

** Some of you tend to divide both sides of the equation by the letter, for eg, divide by 2x or divide by x. You can divide both sides by a number, say 4, but not an alphabet. By dividing by x, you are actually rejecting one value of the final answer.

** Some of you tend to forget to equate one side of the eqn to 0. For instance, if we have x^2 -x = 6, we got to bring the 6 over to the left hand side so that the right hand side of the equation is 0.

** Another common mistake lies in the working of the cross factorisation.. for instance if we have x^2 - x - 6... in our cross factorisation working, we tend to write x instead of -x , or 6 instead of -6. So please be extra careful !!

** Say if we have 4x = 7, when we bring over the 4, it should be 7/4, not 4/7, not 7/-4. Take note!

** Remember that anything multiplied to 0 is still 0!!!!!

** If we have 7(x+1)^2, we always expand (x+1)^2 first then multiply it by 7. DO NOT multiply 7 in to get (7x+1) then square it. It's wrong!

Hope i have pointed out all common mistakes. If i have accidentally missed out your careless mistake, please do your peers a favour by posting it in the comments area so that all of us can learn together!!!

All the best for your test! 2E2, it's time to buck up and get ready for Common Test!! Really hope to see all of you improve!! :)

Regards
Miss Gina