See the following

quadratic solver.sm (6,42 KiB) descargado 1287 vez(es).


Note how second root from solve function generated a fraction containing
large numbers with minor error. This compares with actual which is a
simplistic decimal.

Is there a work-around to obtain the correct decimal result?

Your fractional didn't survive as soon as I asked
for 15 decimals in your 'r1'.

quadratic solver.sm (8,77 KiB) descargado 1318 vez(es).

Simply change the optimization of [MATH]solve(f(x),x)[/MATH] from symbolic to numeric.