Y= ax² -4x +3
-b/2a is x - coordinate of the vertex,
line of symmetry x=-2, x=-2 is a coordinate of the vertex also, because the line symmetry has vertex.
x= -b/2a
x= -2, b= -4
-2=-(-4)/2a
-2=4/2a
-2=2/a
a=2/(-2)=-1
a= - 1
D. 2x+3 is the right answer
Answer:

Step-by-step explanation:

4x - 4y = -36
3x + 4y = 8
7x = -28
/7 /7
x = -4
-4 - y = -9
+4 +4
-y = -5
/-1 /-1
y = 5
(-4 , 5)