Question 1041402
2x^2-7x-9
a=2;b=-7;c=-9. b^2-4ac=49+18=67. This will have two real intercepts
{{{graph(300,200,-10,10,-10,10,2x^2-7x-9)}}}
x^-4x+4
a=1;b=-4;c=4.  b^2-4ac=0
This is one root of multiplicity 2. The factors are (x-2)^2, and the graph will "bounce" at the root of x=2
{{{graph(300,200,-10,10,-10,10,x^2-4x+4)}}}
4x^2-3x-1
a=4;b=-3;c=-1 b^2-4ac=9+16=25.  Two real roots
{{{graph(300,200,-10,10,-10,10,4x^2-3x-1)}}}
x^2-2x-8
a=1;b=-2;c=-8  b^2-4ac=4+31=36.  Two real roots.
{{{graph(300,200,-10,10,-10,10,x^2-2x-8)}}}
3x^2+5x+3
a=3;b=5;c=3 b^2-4ac=25-35=-11. No real roots
{{{graph(300,200,-10,10,-10,10,3x^2+5x+3)}}}