Question 773274
<pre>
{{{2*x^2 + 7*x - 4 = 0}}} is a standard quadratic equation which we can solve 
through factorization.
Rewrite the equation, splitting 7x as 8x - x
{{{2*x^2 + 8*x - x - 4 = 0}}}
{{{2*x(x + 4) - 1(x + 4) = 0}}}
{{{(2*x - 1)*(x + 4) = 0}}}
So the 2 roots are:
{{{2*x - 1 = 0}}} or {{{x = 1/2}}}
{{{x + 4 = 0}}} or {{{x = -4}}}
Hope you got it:)
See the graph below:
*[invoke quadratic "x", 2, 7, -4 ]
</pre>