A parabola intersects the x-axis at x=3 and x=9. What is the x-coordinate of the parabola's vertex?

6

Step-by-step explanation:

If the graph intersects the x-axis, then there is an x-intercept at that point. So, we know that 3 and 9 are the x-intercepts of the parabola.

Parabolas can only have 0, 1, or 2, x intercepts. The x coordinate of the vertex will be the average of the x coordinates of the x-intercepts, since the vertex will be in the middle of the 2 x intercept points.

Take the average of 3 and 9:

(3 + 9) / 2

12 / 2

= 6

The x coordinate of the vertex is 6.

5+2x=a

asdasdsaadsaddsasds

94

step-by-step explanation:

average the numbers and use a variable to figure out the minimum to get a 90.

(79+94+91+92+x)/5=90

x = 94