Question 1200511
h of the 50%
50-h of the 40%
Result Wanted, 50 gallons of 46%


{{{50h+40(50-h)=46*50}}}, to account for amount of pure antifreeze.


{{{50h-40h+40*50=46*50}}}

{{{(50-40)h=46*50-40*50}}}

{{{h(50-40)=50(46-40)}}}

{{{highlight_green(h=50((46-40)/(50-40)))}}}---------The computations were not yet done, so you can think about the form of this expression for variable h.  ....
Now, compute h, and use it to evaluate 50-h.