1. ## Quadratic Equations and kinetics

I think this is the right section to post this but im not 100%

Find the time required for a train to reach 100m if Vo=20m/s (not sure how to do subext) and acceleration is $.5m/s^2$
$
s=20t+(1/2).5t^2
$

As far as i know, this is solved using the quadratic formula. How would i go about putting this equation into quadratic form so i can use the quadratic formula?

2. Originally Posted by mode
$
s=20t+(1/2).5t^2
$

As far as i know, this is solved using the quadratic formula. How would i go about putting this equation into quadratic form so i can use the quadratic formula?
make $a = \frac{1}{2}\times 0.5 = 0.25$ , $b= 20$and $c= 0$

3. would the 2nd number always be a? and would the first nuumber always be b?

4. Originally Posted by mode
would the 2nd number always be a? and would the first nuumber always be b?
No, for $at^2+bt+c = 0 , t= \frac{-b\pm\sqrt{b^2-4ac}}{2a}$

Do you follow?

5. yea i do know i was just confused as to where the numbers would go in the quadratic form. But a little thinking has pulled me through but thanks for your help