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kurosaki69
Sep2-07, 04:49 PM
1. The problem statement, all variables and given/known data

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



3. The attempt at a solution

bel
Sep2-07, 04:50 PM
There's no "x" in the equation, but if you are solving for "t", use the quadratic equation.

rootX
Sep2-07, 04:51 PM
should be using this formula
http://upload.wikimedia.org/math/3/e/a/3ea647783b5121989cd87ca3bb558916.png

kurosaki69
Sep2-07, 04:55 PM
k thanx but im still kind of stuck is -8.00t b and -4.90 a and 30 c. for the quadratic formula

bel
Sep2-07, 04:58 PM
The determinant of the second degree equation is positive, which thereby yields two distinct real roots.

kurosaki69
Sep2-07, 04:59 PM
im sorry but can u explain that simplier

bel
Sep2-07, 05:05 PM
Well, the thing inside the radical sign, it is positive, sqrt((-8.00)^2-4*(-4.90)(30))=sqrt(652), which is real.

kurosaki69
Sep2-07, 05:12 PM
thanks a bunch