I will do my best to explain this “ x method “ I use
Basically, two factors of the first and last number must multiply together to sum up to equal the middle number
1 X 12
1 4
(x+12) (x+4)
Hope this helps!
You need to find x so that then you can do it and you didn’t share a answer so how are we supposed to know??
A group is around 4-8 people so i would go with 4 at first. 4x32= $128 so that’s your answer, hopefully!
Let 
be the volume of 20% solution, 
the volume of the 60% solution. We want a total volume of 400 mL in the final mixture, so
Each mL of either solution will contribute a corresponding concentration, and in the final mixture we want the 400 mL to have a 40% concentration, which means we should also have
Solve the system and we get 
.
First, you must know these formula d(e^f(x) = f'(x)e^x dx, e^a+b=e^a.e^b, and d(sinx) = cosxdx, secx = 1/ cosx
(secx)dy/dx=e^(y+sinx), implies <span>dy/dx=cosx .e^(y+sinx), and then
</span>dy=cosx .e^(y+sinx).dx, integdy=integ(cosx .e^(y+sinx).dx, equivalent of
integdy=integ(cosx .e^y.e^sinx)dx, integdy=e^y.integ.(cosx e^sinx)dx, but we know that d(e^sinx) =cosx e^sinx dx,
so integ.d(e^sinx) =integ.cosx e^sinx dx,
and e^sinx + C=integ.cosx e^sinxdx
finally, integdy=e^y.integ.(cosx e^sinx)dx=e^2. (e^sinx) +C
the answer is
y = e^2. (e^sinx) +C, you can check this answer to calculate dy/dx
