The formula v = u +at gives the final velocity of an object as it accelerates. If v= 35, a=4 and t=5 then find u

First off, you would start by substituting in the numbers that you already know.
Therefore you get: 35 = u + (4 x 5)
Remembering BODMAS you would then look at the equation and solve the brackets first to give:
35 = u + 20
Next you would rearrange to make u the subject which would give:
35 - 20 = u (Remember when you move a number to the other side of the = sign it is multiplied by -1). Therefore you get: u = 15.
Then to be sure you could put your answer back into the original equation: v = 15 + (4 x 5) which gives:
v = 35 which is the same as what v is equal to in the question. Therefore this is correct.