Tuesday, September 23, 2008

Thanks a lot for choosing me for the blogger -_- but anyways... today the teacher asked if anyone that doesn't have a blogging account please make one asap. Also we had to hand in our homework which was called Completing the square exercise.

After that was done we worked on the questions on that exercise.

so she explained that if you had gotten the top formula and you were trying to find the vertex that you would have to re-write it into that formula under the top formula.

Root : y = 0
so if you were looking for the root you would have to look for where "y" = to ZERO

so you would have to re-arrange your formula into a (x-h)² = -k

  • vertex is (-h , k)
  • root : -b ± √ k/a ( negative b, plus or negative square root of k over a )
  • then you find the square root of "k" over "a" and add h

how to make a perfect square:

The question we worked on today was:
y= 2(x - 3)² -5
on the question we found out that, (3 , -5) was the vertex

one of the roots is going to be at 3 and the other ones is around 1 :

* if you have a positive in front of the ax² your parabola will be facing upwards and if negative it will be facing downwards.

we looked at math question we had looked at before and we drew it:

^ what i did up there is i found "b" and it was 64 and plugged it in and than multiply everything by 5 since h-6 was already divided by 5 so it cancels out so i found what the t and the 'h'

the teacher said that:
make sure what the question is before you start on the question cause you might be finding the wrong thing. this question was asking for the vertex and the time only so you didn't have to find the root.

last but not least make sure you guys study we have a pre-test tomorrow and the actual test on Thursday

hope you guys understood everything ☺


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