- #1
thetexan
- 269
- 11
I know everyone here must know this but it is a new revelation to me and very interesting. But I have a question about the reason behind the following...
Take ##x^2+10x+10## for example.
Any coefficient of ##x^2## modifies the "zoom" of the parabola, for lack of a better word, and determines whether it is a "up" parabola or "down" parabola.
The x term and it's coefficient determines the center of the parabola. The center is always 1/2 of the inverse of the coefficient. For example 10x results in a centerline of -5.
The constant gives the y intercept.
The x2 coefficient is related to the x coefficient in this respect...the parabola centerline at x will always be 1/2 of inverse of the x coefficient divided by the coefficient of the ##x^2## coefficient!
For example...
##2x^2 + 60x + 20## results in...
1. a y intercept of 20
2. a parabola centerline of ##( (+60/2)*-1) / 2 ## or -15
I'm trying to understand why this should be. Why or how does the ##x^2## coefficient of 2 have any relationship with the x coefficient of 60 such that the two together determine the parabola centerline?
Any insights would be appreciated.
Thanks,
tex
Take ##x^2+10x+10## for example.
Any coefficient of ##x^2## modifies the "zoom" of the parabola, for lack of a better word, and determines whether it is a "up" parabola or "down" parabola.
The x term and it's coefficient determines the center of the parabola. The center is always 1/2 of the inverse of the coefficient. For example 10x results in a centerline of -5.
The constant gives the y intercept.
The x2 coefficient is related to the x coefficient in this respect...the parabola centerline at x will always be 1/2 of inverse of the x coefficient divided by the coefficient of the ##x^2## coefficient!
For example...
##2x^2 + 60x + 20## results in...
1. a y intercept of 20
2. a parabola centerline of ##( (+60/2)*-1) / 2 ## or -15
I'm trying to understand why this should be. Why or how does the ##x^2## coefficient of 2 have any relationship with the x coefficient of 60 such that the two together determine the parabola centerline?
Any insights would be appreciated.
Thanks,
tex