Write the quadratic equation in Vertex form with vertex (4 8) and passing through the origin.
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Vertex = (4,8)
Passing through the origin = (0,0)
Vertex form:
y= a (x-h)^2+k
(h,k) is the vertex:
y= a (x-4)^2+8
Replace the (x,y ) by the origin coordinates
Solve for a
0= a (0-4)^2+8
-8 = a(-4)^2
-8 = a 16
-8/16 = a
-1/2 = a
y=-1/2 (x-4)^2+8