P=(3a+5)/(4-a) Make a the subject

P=(3a+5)/(4-a)First of all we need Get rid of the denominator, we do this by multiplying both sides by (4-a)This leaves P(4-a)=3a+5 (as any term multiplied by the denominator leaves only the numerator)The next step is to expand the bracket, which leaves us with 4P-aP=3a+5.Now we need to put all "a" terms on one side of the equation and all "non a" term on the other. To do this we can add aP to both sides and minus 5 to both sides. This leaves us with 4P-5=3a+aP.Now we have a as a common term on the right side so we can factorise to move a outside of the bracket leaving 4P-5=a(3+P)Now the final step is to divide both sides by (3+P) to leave a as the subject.This leaves us with the final correct answer of (4P-5)/(3+P)=a