param N := 2;

var x{1..N};
param B{1..20};

minimize f:
-1*(B[1]+B[2]*x[1]+B[3]*x[1]^2+B[4]*x[1]^3+B[5]*x[1]^4+B[6]*x[2]+B[7]*x[1]*x[2]+B[8]*x[1]^2*x[2]+B[9]*x[1]^3*x[2]+B[10]*x[1]^4*x[2]+B[11]*x[2]^2+B[12]*x[2]^3+B[13]*x[2]^4+B[14]/(x[2]+1)+B[15]*x[1]^2*x[2]^2+B[16]*x[1]^3*x[2]^2+B[17]*x[1]^3*x[2]^3+B[18]*x[1
]*x[
2]^2+B[19]*x[1]*x[2]^3+B[20]*exp(0.0005*x[1]*x[2]));

subject to cons1:
x[1]*x[2] - 700.00 >= 0;

subject to cons2:
x[2] - 5.0*(x[1]/25.0)^2 >= 0;

subject to cons3:
54 <= x[1] <= 75;

subject to cons4:
x[2] <= 65;

subject to cons5:
(x[2]-50.0)^2 - 5.0*(x[1]-55.0) >= 0;

data;
var x:=
1	95
2	10;

param B:=
1	75.1963666677
2	-3.8112755343
3	0.1269366345
4	-0.0020567665
5	0.0000103450
6	-6.8306567613
7	0.0302344793
8	-0.0012813448
9	0.0000352559
10	-0.0000002266
11	0.2564581253
12	-0.0034604030
13	0.0000135139
14	-28.1064434908
15	-0.0000052375
16	-0.0000000063
17	0.0000000007
18	0.0003405462
19	-0.0000016638
20	-2.8673112392;
solve;

display x;