Respuesta :

2 times, once at 3 and once at -2

Answer:

Graph of the function touches x-axis twice at 3 and -2.

Step-by-step explanation:

Given : Quadratic function [tex]y= -x^2+x+6[/tex]

To find : How many times does the graph of the function given intersect or touch the x-axis?

Solution :

To find the points graph touch the x-axis i.e, the functions real roots.

Using quadratic formula,

General form - [tex]ax^2+bx+c=0[/tex]

[tex]D=b^2-4ac[/tex]  

Solution is [tex]x=\frac{-b\pm\sqrt{D}}{2a}[/tex]  

Equation is [tex]y= -x^2+x+6[/tex]

where, a=-1 , b=1, c=6

[tex]D=b^2-4ac[/tex]  

[tex]D=(1)^2-4(-1)(6)[/tex]  

[tex]D=1+24[/tex]

[tex]D=25[/tex]

D>0 i.e, 2 real roots exist.

Solution is [tex]x=\frac{-b\pm\sqrt{D}}{2a}[/tex]

[tex]x=\frac{-(1)\pm\sqrt{25}}{2(1)}[/tex]  

[tex]x=\frac{1\pm 5}{2}[/tex]  

[tex]x=3,-2[/tex]  

Therefore, graph of the function touches x-axis twice at 3 and -2.

Refer the attached figure below.

Ver imagen tardymanchester