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In 19 days I will be taking a physics class. I have already taken two algebra classes yet I do not know how to rearrange equations. What are the rules for rearranging an equation. F=m*a, how do you rearrange it so you know what m= ?
t=(Vf-Vi)/a if I wanted to find "a" I would multiply both sides by a, yes? but that would leave me with at=Vf-Vi right? and "a" would not be isolated on one side of the =. what am I doing wrong?HallsofIvy said:You "undo" whatever is done to a. In F= ma, a is multiplied by m. To "undo" that, you do the opposite of "multiply by m"- you divide by m. Dividing both sides of the equation by m, F/m= (ma)/m= a so a= F/m.
An eqaution remains equivalent when you multiply both sides with the same factor, including 0.TD said:b) An eqaution remains equivalent when you multiply both sides with the same factor ([tex] \ne 0[/tex])
You have to pay attention to the parantheses.Serj said:ok I have the equation a=(V2-V1)/t , And I want to make it V2=? . it would be a*V2= (-V1)/t ,is it good so far? but i dont know what to do with "a"
I see what you're saying. I am splitting hairs when I point out that strictly speaking, a = b is preserved under multiplication with zero, which is not covered under your (or, the)definition of equivalent equations.TD said:I thought that in equivalent equations, the solutions have to remain the same.
In that case, you have to exclude 0, no?
why did you out everything except V2 on the other side of the = instead of putting V2 were "a" was and put "a" on the other side?EnumaElish said:You have to pay attention to the parantheses.
a = (V2 - V1)/t
at = V2 - V1
at + V1 = V2
ek's explanation is right:Serj said:why did you out everything except V2 on the other side of the = instead of putting V2 were "a" was and put "a" on the other side?
why did you multiply "t" and "a"?
if "t" was the numerator, would you still multiply it with "a"?
You are wrong at the second line.Serj said:...d/V=Vt/V+1/2 at^2
d/V=t +1/2 at^2
First, you made an error in your first step. If you divide by V, you have to divide EVERYTHING by V, so your second equation would be:Serj said:I've got a problem I don't know how to rearrange. d=Vt+1/2 at^2 ,i'm supposed to find out what t equals.
d/V=Vt/V+1/2 at^2
d/V=t +1/2 at^2
2d/V=t +2*1/2 at^2
2 d/V=t + at^2
(2 d/V)/a=t + at^2/a
(suare root of)(2 d/V)/a=t + (square root of)t^2
(suare root of)(2 d/V)/a=t +t
((suare root of)(2 d/V)/a)/2=2t/2
((suare root of)(2 d/V)/a)/2=t
What did I do wrong? how do I fix it so Im not dividing fractions