Answer:
<u>30 gallons solution 4% and 10 gallons solution 8%</u>
Step-by-step explanation:
<h3>x•4%+y•8%=40•5% </h3>
<em><u>4x+8y=40•5 and x+y=40</u></em>
x=40-y
4(40-y)+8y=200
160-4y+8y=200
4y=200-160
4y=40 => y=10 (gallons solution 8%)
=> x=40-10=30 (gallons solution 4%)
30 gallons solution 4% and 10 gallons solution 8%
Theres only 4 but the answer is -15
Y is the number of movies
x is the number of hours
It takes 2 hours per movie
Thus:
y = x/2
2y = x
x - 2y = 0
The answer is C