Question

Consider the graph of the quadratic graph y=-x^2 -10x+24 ,what is the y-value of the vertex

Answer 1

-51

First, find the axis of symmetry, or the x value where the line switches directions. This is also the x value of the vertex. Find this by using the equation -b/2a. In this case, -10 is b, and 1 is a.

-(-10)/2(1)

10/2

5

So, the x value of the vertex is 5. Now, find the y value by putting the x value back into the equation.

y = -(5)^2 - 10(5) + 24

y = -25 - 50 + 24

y = -75 + 24

y = -51

So, the y value of the vertex is -51.