TRANSPOSITION OF FORMULAE B2

If c =  d(m + f)    make m the subject of the formula.

             (m – f)

Solution

c =  d(m + f)   

         (m – f)

(m – f) x c = d(m + f) x (m – f)   multiply by(m - f) on both sides.

                         (m – f)

(m – f) x c = d(m + f) open the brackets on both sides.

                      

mc – fc = dm + df

mc – dm = fc + df         (collect the terms containing m together)

m(c – d) = fc + df

m(c – d) = fc + df       Divide by (c - d) on both sides.

   (c – d)     (c – d)

m= fc + df      

       (c – d)

Hence  m= fc + df      

                    (c – d)