y is a quadratic function that has vertex at (-1, 6) and y- int. at (0, -1). find the equation for y.
+130516 We have the form
y = a(x - h)^2 + k
Where (h, k) = the vertex = ( -1, 6).....and we know a point on the graph... (0, -1)
So....we can solve for a
-1 = a(-1 - (0))^2 + 6
-1 = a( -1)^2 + 6
-1 = a + 6 subtract 6 from both sides
-7 = a
So....in vertex form, we have
y = - 7( x - (-1) )^2 + 6
y = -7 ( x + 1)^2 + 6
