Question 230075
All I can figure is that they want you to say
{{{x + y}}} liters is the total liters of solution
and {{{y = 50}}} is the other equation (very trivial)
Let {{{x}}} = liters of 20% alcohol solution needed
In words:
(final liters of alcohol)/(final total solution) = 50%
given:
Alcohol in 70% solution:
{{{.7*50 = 35}}}
----------------------
{{{(.2x + 35)/(x + y) = .5}}}
{{{.2x + 35 = .5*(x + y)}}}
{{{.2x + 35 = .5x + .5y}}}
(1) {{{.3x + .5y = 35}}}
and
(2) {{{y = 50}}}