Try the windows character map application.
To solve problems like this spot ways in which you can manipulate the equation(s) you are given, for example, +, -, /, or * is such a way that you end up with either the unknown on one said of the = and the numeric values on the other side. After which the olution is trivial. Or a solvable quadratic.
In the case of your example 24/x = 10-x. Therefore 24 = 10x - x². Therefore -x² + 10x -24 = 0.
Once you get to this point it is a quadratic and can be solved using the formula I'm sure your teacher must have given you (and suggested you memorise for the exam) at some point.
http://en.wikipedia.o...ki/Quadratic_equation