This week, we learnt:
Completing the square!
As you can see, we subtracted both sides by 3, but wait. 5 does not have factors that add up/subtract to get 3! So. We have to do this equation using the "completing the square" method.
We can do this by subtracting the constant on both sides, giving you -3 in this case on the RHS. We then use the "a^2-b^b" method. Because of the 2ab part in the centre, we have to divide 5 by 2, giving us the "b" which is half of 5. BUT. To make both side equal, we have to ADD the "b" to both sides, which is 5/2 in this case. We then factorise and simplify the fractions, giving you the answer :)
(PRACTICE THIS! It is complicated BUT once you get it right, it would be easy for you :))
We can multiply a fraction by (-1)/(-1) and the fraction is still equal.
We also learnt that parabolas are always linked to quadratic equations.
One example of what we learnt:
(Note: Always make y=0)
(Then we factorise)
Therefore, x-3=0 OR x-2=0
Answer is x=3 OR x=2
(Note: We have to write both ORs down. Both of them are answers!)
Done by Kenneth Teh