Question 1037764
x for gallon volume of the 45% and y for gallon volume of the 70%.
{{{system(x+y=150,(45x+70y)/150=55)}}}



A lesson how this works:  <a href="https://www.algebra.com/my/Mixtures%3A-All-in-Symbols.lesson?content_action=show_dev">Mixing two concentrations for known amount of mixture i</a>