The Mathematics of Radio Location Step 1: Intersection of Two Circles
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kill(all);

A : (x)^2 + (y)^2 - 1^2 ;

B : (x-h)^2 + (y-k)^2 - r^2 ;

A = B;

A - B = 0;

C : expand(A - B = 0);

D:rhs(first(solve(C,y)));

substitute(D,y,A);