Prime crashes upon fsolve

[roadrunner]

You can use solve and it get's both solutions without a guess:

solve([(a^2) = (b^2+c^2),b = (ABS((4/3)*c)),a = 7.112],[a,b,c])

returns:

[a = 7.112,b = 5.6896,c = 4.2672],[a = 7.112,b = 5.6896,c = −4.2672]

-road