SOLUTION: could someone please help me with the following question. A formula is given as V=2u+3t�. Change the subject of the formula to t.

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Question 905889: could someone please help me with the following question.
A formula is given as V=2u+3t�. Change the subject of the formula to t.
Answer by Theo(13342) (Show Source):
You can put this solution on YOUR website!
you want to solve for t instead of v.

the original equation is:

v = 2u + 3t^2

subtract 3t^2 from both sides of the equation and subtract v from both sides of the equation to get:

-3t^2 = 2u - v

divide both sides of the equation by -3 to get:

t^2 = 2u/-3 - v/-3

simplify to get:

t^2 = -2u/3 + v/3

simplify further to get t^2 = (-2u+v)/3

take the square root of both sides of the equation to get:

t = plus or minus sqrt((-2u+v)/3)

problem is now solved for t instead of v.

you can confirm you did it correctly by seeing that both equations are compatible with each other.

here's what i did:

start with t = plus or minus sqrt((-2u+v)/3)

let v = 400 and let u = 50 and solve for t.
these numbers were chosen so that the solutions would be integers.

you get t = plus or minus 10

now start with v = 2u + 3t^2 (your original equation)

let u = 50 and t = plus or minus 10.

when t = 10, you get v = 100 + 3*100 = 400

when t = -10, you get v = 100 + 3*100 = 400

the two equations are compatible with each other which confirms that you did the translation from solving for v to solving for t successfully.