Question 1039805
{{{ y = x^2 + 5x }}}
The discriminant is:
{{{ b^2 - 4*a*c }}}
The general equation for a quadratic has the form:
{{{ y = a*x^2 + b*x + c }}}
{{{ a = 1 }}}
{{{ b = 5 }}}
{{{ c = 0 }}}
{{{ b^2 - 4*a*c = 5^2 - 4*1*0 }}}
{{{ b^2 - 4*a*c = 25 }}}
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The discriminant is real and positive, and it is not zero
also, the discriminant is a perfect square. When you 
plug the discriminant back into the quadratic
formula, you have 2 real, rational roots
{{{ x = ( -b +- sqrt( b^2-4*a*c ))/(2*a) }}}
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Here's the plot of the equation:
{{{ graph( 400, 400, -10, 10, -10, 10, x^2 + 5x ) }}}