How Do You Rearrange Kinematic Equations Effectively?

[Siege]

I already typed a long drawn out post, so I am going to simplfy it.

I am having trouble using algebra to rearrange equation.

For Example,

v=d/t
And so, to solve for both t and d, I do the following

vt=d/t x t
vt=d
vt/v=d/v
t=d/v

I have difficulty with most if not all the other equations. For example, the formula for acceleration.

a=Vf-Vi/t
Solve for t

a=Vf-Vi/t
at=Vf-Vi/t x t
at + Vi=Vf -Vi + Vi
at+Vi=Vf
Vf-Vi/a=t

This is my attempt at it. I multiplied by t, then eliminated the negative, and finally divided by a.

Thank you ahead of time!

 

[rock.freak667]

Yes those are correct.

For the second one, you could have done it simpler instead of expanding out:

a=(v_f-v_i)t

multiplying both sides by 't'

at=(v_f-v_i)

divide both sides by 'a'

t=(v_f-v_i)/a

 

[Siege]

Thank you very much.

Are there any tricks to rearranging equations? or rules to follow?