The new mixture has a total volume of 5 L + 9 L = 14 L.
70% of the 5 L alcohol solution is alcohol, so that it contributed 3.5 L of alcohol to the mixture. The pure water contributed no alcohol. So in the mixture, the concentration of alcohol is
3.5 L / 14 L = 0.25, or 25%
An integer is all whole numbers and zero, are the numbers you are talking about negatives?
the problem isnt that hard. you need to do the distributive property or FOIL with (m+3) four different times. The answer would be
M^4 + 12M^3 +54M^2 +108M +81
