4ac\). And the types of root the equation has can be worked out as follows: If \({b^2} - 4ac\textgreater0\), the roots are real and unequal (diagram A) If \({b^2} - 4ac = 0\), the roots are real ...

The second diagram has one root and the third diagram has no roots. The discriminant can be used in the following way: \({b^2} - 4ac\textless0\) - there are no real roots (diagram 1 ...