What is the value of m in the equation y=x^2+mx-9 with vertex (-1.5,-11.25)

3

Step-by-step explanation:

Step 1:

Let the given equation be

Step 2:

Applying the  given vertices and simplifying  we will get m

-11.25 = (-1.5)² +m(-1.5) -9

-1.5m = -11.25 + 9 - 2.25

         = -4.5

m = (-4.5) / (-1.5)

    = 3