Hello!
So you figure that 7/10-5/10=2/10 that leave you with 1/5 left over. So if you take that into effect, all you have to do it multiply those 3 gallons by 5. Which gives you 15. So, your answer would be 15 gallons.
I hope this helped!
I am, yours most sincerely
SuperHelperThingy
D
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Well, so the x+5y= 0 you can make this into x=-5y and then plug this in into ( y=9-2x) the -2x , which these would become y=9-2(-5y) simplify and equals to y=9+10y. Then you simplify much smaller y=-9. Now that you have the y number you just plug this in into x=-5y, which these becomes x=-5(-9) and the answer is x=45. At the end you just need to find the x and y, so the answer is x=45 and y=-9 . Hopefully this would make this much easier to you.
I might be able to give you a hand here!
Answer: -9sinx + 3cosx + 4sec^2x
