Factor to solve the equation
3x^2+10x-98=0
This is not geometry. There are no rational integer solutions to this equation.
The roots are
x = (1/6)[-10 +35.72..] = 4.287..
and
x = (1/6)[-10 -35.72..] = -7.620..
One way of factoring it would be
3*(x-4.287)(x+7.620) = 0