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.