If you take a varible, lets say x, and times that by your mom. You will get y^2. After that, take ur mom and divide that by ur dads ding dong. Now they don't give us the formula to find out how long, creamy and wet your dad's ding dong is so we use the formula, busty step sis + step bro = BIG DING DONG, to get (x^69)+12 as ur dads ding dong. Now add ur mom with ur dad, y^2+(x^69) to get a child, 6969699696.
Hope this helps :)