1. 1 Mathematics Exercises Sharing KONG Ching-wah

2. 2 A case 7x + 4x =11x mx + nx =(m + n)x 7x + 4x = 15x + 23x = 11x + 36x = 38x + 25x = 14x + ax = ax + bx =

3. 3 Assignment is: - By order - No choice - Routine work - Boring - Too easy/too difficult - Not align with assessment

4. 4 12 -35 = -65 - (37) = 23 + (-37) = -28-(-39) = -16 - (-37) = 18 - (-7) = -6 +(-77) = 26 - (-47) = -36 - (-57) = -16 +(-37) = -36 - 57 = (-36) - (-57) = -37 -(-18) = -22 -37 = -47 -(-18) =

5. 5 -28-(-39) = 5 – 2 = _____ 5 – 1 = _____ 5 – 0 = _____ 5 – (-1) = ____ 5 – (-2) = ____ 5 – (-3) = ____ 5 – (-4) = ____ 5 – (-5) = ____ 5 – (-6) = ____ 5 – (-7) = ____ 8 –(-12) = ____ 18–(-24) =____ 5 – (-7) = _____ 4 – (-7) = _____ 3 – (-7) = _____ 2 – (-7) = _____ 1 – (-7) = _____ 0 – (-7) = _____ -1 – (-7) = _____ -2 – (-7) = _____ -3 – (-7) = _____ -8 – (-12) = ____ -18–(-24) = ____

6. 6 28-3635 +- - +- 12 -26 -1729 + +- - -22 -33 -19 5213

7. 7 [ － ]( ) -5 [ / ]

8. 8 4ab + 3a 2 b + 2ab Use, and to divide the following expressions into three groups. xy 3x 2 y xy 2 4xy 2xy 2 3x 2 y -5xy -2x 2 y 16xy -23x 2 y 43x 2 y -11xy 2 7xy -16xy 89xy 2 5xy 2 -3x 2 y -34x 2 y 25xy -19xy 2 -20x 2 y

9. 9 2ab + 3a 2 b How many “7”s are there? 2(7) + 3(7) = ___________ How many “x” are there? 2x + 3x = _____________ How many “xy” are there? 2xy + 3xy = ___________ Can we add them up? 2xy + 3x 2 y = ___________ = ___________

10. 10 (4x － 3) + ( － 7x ＋ 9) = 2x + x = 2x + (-x) = 2x + (-2x) = 2x + (-3x) = 2x + (-5x) = 2 + 5 = 1 + 5 = 0 + 5 = -1 + 5 = -2 + 5 = Group the like terms. (3x 2 +5x-8) + (-5x 2 -7x-6) =

11. 11 120 o OA B Find the area of sector OAB 120 o = ------- of a circle ? 120 o The area of sector OEF is ? 90 o 3cm O E F Find the area of the shaded part. 3cm O E F 90 o 6cm

12. 12 3cm 4cm 12cm Find the total surface area of the following object. 3cm 4cm 12cm Total Area No. of piece AreaDimension

13. 13 Find the total surface area of the following object. 3cm 4cm 12cm

14. 14 A Story Mode I can only do the operations of “multiply by 2” and “divided by 2” and I can do the multiplication of all numbers. This is the way I do 25(47) Divided by 2 Multiply by 2 25* 47  12 94 6 188 3* 376  1* 752  47 + 356 + 752 = 1175 25(47) = 1175 John 1.Find the way that John did his calculation. 2.Why it works in this calculation? 3.Is this method applicable to all operation of multiplication of two numbers?

15. 15 When the sum of all the digits in a number is divisible by 3, this number is divisible by 3. Do you believe? Give your reason. Believe or not?

16. 16 The Design: - Of own learning - Of own choice - Learning task - Variety - Suitable challenge - Cross topics - Learn new things and strengthen the old.

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