Completing the Square 2/5/08

Maxx Scribe

Today we learned about completing the square method.
In problems PG 23 and PG 24 you found out how to change a quadratic function from the standard form
(standard form) y= ax^2+bx+c (graphing form) y=a(x-h)^2+k
which is to figure out the vertex by using the average of the x- intercepts and then to substitute it the coordinates of the vertex for h and k.

This is what Completing the Square method looks like.

Its similar to the box method that we used before but a bit different. Everything is pretty self explanatory because it works the same way.

Scribe Post February 1st

On February first my group and I headed downstairs to finish off the rest of the trials and gather the data we needed. We had already finished the long jump for Miller, so Doyle was up. We decided where Doyle was going to jump from and measured from there where we thought the balloon should be. 156 inches away, we measured the height of the balloon, to set the height of the parabola at 78 inches. He sprinted, and jumped forward, barely touching the balloon, and we recorded the data. Next up was Ed, and we set the balloon first at 118 inches away, keeping the height the same, 78 inches. We had to bump the distance the balloon was from Ed's point of depature down to 98 when he couldn't quite make it. The second time trying he actually jumped off of his own two feet the and toppled over in mid air. We laughed, but continued on with the experiment until we acquired the appropriate data. Finally I was up, and I could make it to about 132 inches away from my point of jumping, with the balloon at the same height as before, 78 inches. Finally once we collected all our data, we headed back upstairs. I had Miller photocopy five copies of the data for everyone. There was a problem as to how to create a parabola from the data acquired, seeing as it wasn't a perfect parabola everytime we jumped. I consulted Mr. Rochester and he stated that he wants us to imagine it like we're starting from the negative of the distance we jumped, and the vertex of the parabola is zero and the height of the balloon, and then the other x-intercept is the positive of the distance we jumped. So if I were to make my graph of my long jump, the vertex would be (0,78) and the two x-intercepts would be (-132,0) and (132,0).

The next scribe will be... Maxx Kim.