Solving for x in 0=−(4.90 m/s^2)t^2 -(8.00 m/s)t + 30m

[kurosaki69]

Homework Statement

0=−(4.90 m/s^2)t^2 -(8.00 m/s)t + 30m
i am asked to solve for x but having problems

Homework Equations

The Attempt at a Solution

 

[bel]

There's no "x" in the equation, but if you are solving for "t", use the quadratic equation.

 

[rootX]

should be using this formula
http://upload.wikimedia.org/math/3/e/a/3ea647783b5121989cd87ca3bb558916.png

 

[kurosaki69]

k thanks but I am still kind of stuck is -8.00t b and -4.90 a and 30 c. for the quadratic formula

 

[bel]

The determinant of the second degree equation is positive, which thereby yields two distinct real roots.

 

[kurosaki69]

im sorry but can u explain that simplier

 

[bel]

Well, the thing inside the radical sign, it is positive, sqrt((-8.00)^2-4*(-4.90)(30))=sqrt(652), which is real.

 

[kurosaki69]

thanks a bunch