Solving Basic Physics Problem: Help with x=8.0m/s*5.0s+ .5*3.0m/s^2*(5.0s)^2

[mrserv0n]

Hi I am studying for this first physics test and having trouble.

heres the equation I am using to find x and I am sure its right but i can't seem to get the answer they do

x=8.0m/s*5.0s +.5 * 3.0m/s^2 * (5.0s)^2 = 77.5

I am not getting the 77.5

8 *5 = 40

3.0 x 5.0 = 15

15 * .5 = 7.5

so 40 + 7.5 = 47.5

I have a feeling that it has something to do with the time being squared buy my algebra sucks.. can someone explain this solution.

 

[Valhalla]

the equation is $$x=\frac{1}{2}at^2+v_ot$$ you forgot to square the time when multiplying against acceleration

 

[vaishakh]

What is the question? what is the problem with things you have done? Pls be specific.

 

[HallsofIvy]

Hi I am studying for this first physics test and having trouble.

heres the equation I am using to find x and I am sure its right but i can't seem to get the answer they do

x=8.0m/s*5.0s +.5 * 3.0m/s^2 * (5.0s)^2 = 77.5

I am not getting the 77.5

8 *5 = 40

3.0 x 5.0 = 15

15 * .5 = 7.5

so 40 + 7.5 = 47.5

I have a feeling that it has something to do with the time being squared buy my algebra sucks.. can someone explain this solution.

x=8.0m/s*5.0s +.5 * 3.0m/s^2 * (5.0s)^2 = 77.5

Yes, it is "the time being squared"- you didn't square! What is 5²?