Simple Equation Set, No Solution

Perhaps this can help:

eq1:r1*theta = 6*%pi;
eq2:r2*theta = 12*%pi;
eq3:sqrt((r2-r1)^2-3^2) = sqrt(6^2-3^2);
s:solve(eq3,r1);
-----------------------------> you get      [r1=r2-6,r1=r2+6]
/*case 1 */
solve([s[1],eq1,eq2],[r1,r2,theta]);
-----------------------------> you get    [[r1=6,r2=12,theta=%pi]]
/* case 2 */
solve([s[2],eq1,eq2],[r1,r2,theta]);
-----------------------------> you get [[r1=-6,r2=-12,theta=-%pi]]

Alternatively....

to_poly_solve([eq1, eq2, eq3],[r1,r2,theta]);
------------------------------> %union([r1=-6,r2=-12,theta=-%pi],[r1=6,r2=12,theta=%pi])

Best
________________________________________________________________
Jose Sanchez-Marin.
 Universitat de Valencia.
 Institut de Ciencia Molecular (ICMol).
 Cat.  Jose Beltran Martinez, 2				Phone: +34 96 354 4444
E-46980 Paterna							FAX:   +34 96 354 3576	            
 Spain 				   					e-mail: Jose.Sanchez at uv.es	   
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