<span>A ball is thrown at a 30 degree angle above the horizontal with a speed of 10 ft/s. After 0.50s the horizontal component of it's velocity will be the same. In a projectile motion the horizontal component of the velocity is said to be constant. Therefore, it will be equal to the initial velocity.</span>
        
             
        
        
        
Answer:
A.
Step-by-step explanation:
 
        
                    
             
        
        
        
First we have to find the vertex (h,k) h is also x and it also is the a xis symmetry 
1st: group the number 
(X2+6x)-9
2nd: use b/2 
6/2 = 3 , 3^2= 9
(X2+6x+9)-9-9
(X2 + 3)-18
Vertex is 3,-18 so the symmetry is 3