# system of equations

Posted 2 months ago
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 Hi To solve the system : x=1700/E^(y/15.5) x=180/E^(y/93.3) I was trying : Solve[x==1700/E^(y/15.5)&&x==180/E^(y/93.3),{x,y}] How can I solve this system with Wolfram Language?
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Posted 2 months ago
 Here is some examples from my code : ClearAll["Global*"]; eq = Solve[ masaTotal - 1/4*masaApa == 2050 && masaTotal - 1/2*masaApa == 1450 && masaTotal - masaApa == masaVas, {masaTotal, masaApa, masaVas}, PositiveIntegers] // Flatten ClearAll["Global*"]; eq1 = 5*k1 - 4*k2 == 108; eq2 = 5*k3 - 4*k4 == 0; eq3 = 5*k5 - 4*k6 == 36*5; eq4 = k1 + k2 == 36; eq5 = k3 + k4 == 36; eq6 = k5 + k6 == 36; mySol = Solve[ eq1 && eq2 && eq3 && eq5 && eq4 && eq6, {k1, k2, k3, k4, k5, k6}, Reals] // Flatten Modify them
 Hi Luis,Since both of the RHS equal x, there is no need for x. Solve[Rationalize@{1700/E^(y/15.5) == 180/E^(y/93.3)}, y, Reals] (* {{y -> -((28923 (2 Log[3] - Log[5] - Log[17]))/1556)}} *) Use N to get the a numeric result (* {{y -> 41.7381}} *) 
 If you are only interested in the Real solution then FindRoot[x==1700/E^(y/15.5)&&x==180/E^(y/93.3),{{x,0},{y,0}}] instantly returns {x->115.077,y->41.7381}