Question 150261
4X^2+11X-20=0
{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}} 
X=(-11+-SQRT[11^2-4*4*-20])/2*4
X=(-11+-SQRT[121+320])/8
X=(-11+-SQRT441)/8
X=(-11+-21)/8
X=(-11+21)/8
X=10/8
X=5/4 ANSWER.
X=(-11-21)/8
X=-32/8
X=-4 ANSWER.