I still got it!

Anyone recognise the formula?

I just spent 20 minutes converting the formula…

d = M-((M/2)+7)


M = 2(d+7)

I still got it baby!

(Even if it would have taken me about a 10th of the time back in high school :))

The steps are…

d = M-((M/2)+7)
M = d+((M/2)+7)
M = d+7+(M*0.5)
M-(M*0.5) = d+7
(This one took me ages)
0.5*M = d+7
M = 2(d+7)

Now, does anyone recognise the base formula?