Question 730145
A chemist is going to mix some L% acid with some H% acid in order to make M Liters of T% acid. How many liters of the L% acid will he use? 


Let u = liters of L% acid, and v = liters of H% acid.


This is the system based on the description:
{{{(Lu+Hv)/M=T}}} and {{{u+v=M}}}.  
Solve for u and v.  The given question asks for u.