Make x the subject of the following formula: 5(3x -2y) = 14 - 2ax

(1) 5(3x - 2y) = 14 -2ax 15x - 10y = 14 - 2ax (2) 15x +2ax -10y = 14 15x + 2ax = 10y + 14
(3) x(15 + 2a) = 10y + 14 x = (10y + 14) / (15 + 2a)
To asking us to make x the subject of a formula, the question really just wants us to write an equivalent of the same formula but in the format :
'x = ...'
In step (1) we are simply expanding all of the brackets to give ourselves the clearest, most simplified view of all of the different variables and constants.
In step (2) we now start to separate the different variables, as we are trying to put everything in terms of x. This involves adding/ subtracting from both sides (so everything is still even) until we have all of the x variables on the left hand side, and everything else on the right hand side.
In step (3) we are now looking to do almost the reverse of step (1) by finding the common multiple between all of the components on the left hand side of the equals sign. Since everything on that side is a multiple of x, we can bring the x outside of the brackets, finally isolating the variable we need. To get the x by itself, we then divide both sides by the contents of the brackets, giving us our answer.