Sunday, November 19, 2006

Great Algebra Problems is a pretty cool site; though it is subscription based, it has a large number of free problems here is their Algebra Page

There problems are remarkably similar to the SAT

Canadian Math Problems

This is really good, the SAT problems have the same concepts as these problems:

Canadian Math Problems

ABP - Always Be Practing!

Tuesday, November 07, 2006

b is backwards: Parabola - bx

Tutoring this weekend, I reviewed the standard equation of a parabola:

ax2 + bx + c = 0

If you read my last posting on parabolas the constant "b" which is multiplied by x controls the movement of the parabola left and right in relation to the y axis.

If b = 0; then the parabola is centered exactly on the y axis

But if b > 0 (positive), the parabola shifts to the left.

Obviously if b < 0 (negative), the parabola shifts to the right

Looking at this normally, it just looks backwards - but it is true.

So remember, b is backwards.