Respuesta :
The x intercepts are determide when you calculated the equation when y=0
To find the x-coordinate of the vertex you have to apply the next formula:
[tex]x=-\frac{b}{2a}[/tex]Where you follow the form of the equation:
[tex]y=ax^2+bx+c[/tex]X-intercep:
1. In this case if we have the equation in the form: x( x - 2) we can know that y=0 when one of the terms is 0:
y=0 when:
x=0x-2=0
x= - 22. y=0 when:
x-4=0
x=4x+5=0
x=-53. y=0 when:
x-1=0
x=1x-5=0
x=5x-coordinate of the vertex:To identify the coeficeints a and b we express the equation in a different form, we have to multiply. Then we can apply the formula to find the x coordinate of the vertex, as follow:
[tex]x=-\frac{b}{2a}[/tex]1.
[tex]y=x(x-2)=x^2-2x[/tex][tex]x=-\frac{(-2)}{2(1)}=\frac{2}{2}=1[/tex]2.
[tex]y=(x-4)(x+5)=x^2+5x-4x-20=x^2-x-20[/tex][tex]x=-\frac{(-1)}{2(1)}=\frac{1}{2}[/tex]3.
[tex]y=(x-1)(x-5)=x^2-5x-x+5=x^2-6x+5[/tex][tex]x=-\frac{(-6)}{2(1)}=\frac{6}{2}=3[/tex]