# What function to use to solve an equation for a variable that's on both sides of the equation?

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Lu Da Silva on 30 Oct 2020
Edited: KSSV on 30 Oct 2020
I need to find s. Every other variable is given; they're all constants except for "e" which is a vector (of 50 given values).
s = a / b
where a = 3 * c^2 * d where c = sqrt(e/(3*d*s))
and b = e - f * g^2 where g = c + (c*s)/(1-s)
I'm confused because s is difficult to isolate manually....
Should I try put the equations all together in order to get s = ........ ? and then put the single s on the right side of the equation so i have an equation == 0 ? What MATLAB function would I have to use to solve it that way? Or is there a simpler manner?
Thanksss
Ameer Hamza on 30 Oct 2020
You said "I need to find s. Every other variable is given". But then you can simply find s using s = a/b.

KSSV on 30 Oct 2020
Edited: KSSV on 30 Oct 2020
syms s a b c d e f g
c = sqrt(e/(3*d*s)) ;
g = c + (c*s)/(1-s) ;
a = 3*c^2*d ;
b = e-f*g^2 ;
eqn = s - a/b==0 ;
Try using solve in eqn.
sol = solve(eqn,s) ;

Ameer Hamza on 30 Oct 2020