<PRE><B>Question 278943</B>
graphically
if the parabola touches the x axis twice there are two solutions
if it touches once there is one solution
if it never touches the x axis there are no real solutions

algebraically
x^+4x+4=0
x^2-2x-3=0
x^2-2x+3=0
check out the determinants in these three equations
*[invoke quadratic &quot;x&quot;, 1, 4, 4 ]
*[invoke quadratic &quot;x&quot;, 1, -2, -3 ]
*[invoke quadratic &quot;x&quot;, 1, -2, 3 ]

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