Question 718946
Plugging in the values rightaway, you have these as a system to solve:


{{{(2x+8y)/75=5}}} and {{{x+y=75}}}, where x is volume of the 2% solution and y is the volume of the 8% solution. 


A few ways to start the rest of the solution process but one way is y=75-x, then do {{{2x+8(75-x)=5*75}}}
{{{2x+8*75-8x=5*75}}}
{{{8*75=-2x+8x+5*75}}}
{{{8*75-5*75=6x}}}
.
Can you continue from here?