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### Completing the square v002

1. Completing the square Completing the square of a quadratic equation. Example 1. Colour edition. singaporestudent.com 1
2. You were asked to complete the square of this quadratic equation: singaporestudent.com 2
3. So we put the equation into our table. 1 2 3 4 singaporestudent.com 3
4. Highlight the part of the equation that contain x2 and x only. 1 2 3 Do not highlight the constant. 4 singaporestudent.com 4
5. Call this expression as ‘p’. 1 2 3 4 singaporestudent.com 5
6. Rewrite 6x as (2)(3) x. 1 2 3 4 singaporestudent.com 6
7. Rewrite 6x as (2)(3) x. 1 2 3 4 singaporestudent.com 7
8. Rewrite 6x as (2)(3) x. 1 2 3 4 We need to do this to apply the formula : a b 2 a 2 2ab b 2 singaporestudent.com 8
9. Rewrite 6x as (2)(3) x. 1 2 3 4 We need to do this to apply the formula : a b 2 a 2 2ab b 2 singaporestudent.com a=x b=3 9
10. 1 Add 32 to p. 2 Call this expression : q 3 4 singaporestudent.com 10
11. 1 Add 32 to p. 2 Call this expression : q 3 4 a b 2 a 2 2ab b 2 singaporestudent.com a=x b=3 11
12. 1 Add 32 to p. 2 Call this expression : q 3 4 a b 2 a 2 2ab b 2 a=x b=3 Now we can apply the above formula. singaporestudent.com 12
13. a b 4 2 a2 2ab b 2 a=x b=3 5 6 7 8 singaporestudent.com 13
14. a b 4 2 a2 2ab b 2 a=x b=3 5 There! We applied the formula. 6 7 8 singaporestudent.com 14
15. 4 since then 5 6 7 8 singaporestudent.com 15
16. 4 since 5 then 6 7 8 singaporestudent.com 16
17. 4 Simplify y. 5 -9 + 5 is 4 6 7 8 singaporestudent.com 17
18. Question : Answer : singaporestudent.com 18