[tex]\\ \sf\longmapsto x^2-4x-5=0[/tex]
[tex]\\ \sf\longmapsto x^2-5x+x-5=0[/tex]
[tex]\\ \sf\longmapsto x(x-5)+1(x-5)=0[/tex]
[tex]\\ \sf\longmapsto (x-5)(x+1)=0[/tex]
[tex]\\ \sf\longmapsto x=5\:or\:x=-1[/tex]
Solution is (-1,0) and (5,0)
Graph attached.
Spare way:-
Use quadratic formula .
[tex]\\ \sf\longmapsto x=\dfrac{-b\pm \sqrt{b^2-4ac}}{2a}[/tex]
[tex]\\ \sf\longmapsto x=\dfrac{-(-4)\pm\sqrt{(-4)^2-4(1)(-5)}}{2(1)}[/tex]
[tex]\\ \sf\longmapsto x=\dfrac{4\pm \sqrt{16+20}}{2}[/tex]
[tex]\\ \sf\longmapsto x=\dfrac{4\pm 6}{2}[/tex]
[tex]\\ \sf\longmapsto x=\dfrac{10}{2}\:or\:\dfrac{-2}{2}[/tex]
[tex]\\ \sf\longmapsto x=5\:or\:-1[/tex]
