Question 469210
{{{3x(2x - 15) = -84}}} divide by 3
{{{2x^2-15x=-28}}}
{{{2x^2-15x+28=0}}}
{{{x = (-b +- sqrt( b^2-4*a*c ))/(2*a) }}} 
{{{x = (-(-15) +- sqrt( (-15)^2-4*2*28 ))/(2*2) }}} 
{{{x = (15 +- sqrt( 1))/4 }}} 
{{{x = (15 +1)/4 =4}}} 
{{{x = (15 -1)/4 =3.5}}}