Question 891405
Implied that legs b,c,a, angles B and C.  Assume C is the right angle and c is hypotenuse.


{{{A+B+C=180}}}
{{{B=180-A-C}}}
{{{B=180-61-90}}}
{{{highlight(B=29)}}} degrees.


Law of Sines will give you length of side a.


{{{a/sin(A)=b/sin(B)}}}
{{{a=b(sin(A)/sin(B))}}}
Substitute the values.
{{{highlight(a=39(sin(61)/sin(29)))}}}