non linear equation, help me solve this please

hi, please help me to solve this

i tried with this

syms x1 x2 x3
eq1 = 12804.724*(0.127-x1);
eq2 = 5894.25*(x2-x3);
eq3 = 98.20*(x3-22);
eq4 = 1.8897*(50-x2)/log(0.127/(0.127-x1));
eq5 = eq1 = eq2 = eq3 = eq4
sol = solve(eq1,eq2,eq3,eq4,eq5);
sol.x1

but it didn't work, please help. Thank you

Answer 1

[Ced]

Hi

1. What does the error say? "The expression to the left of the equals sign is not a valid target for an assignment."

This is referring to eq5 = eq4 = eq3 etc... Matlab does not understand what you want to do in this line

2. I think you misunderstood how solve works. You need to actually pass it equations, and add the variables of interest at the end.

eq1 = 1.2962e+04*(0.127-x1);

is not an equation. This is a variable eq1 with the value 1.2962e+04*(0.127-x1). So, you would need to do something like

sol = solve(eq1==eq2, ... , x1,x2,x3)

3. Last but not least, I think there is a typo in your code, some of the constants do not match the original equations you gave