Find a formula for the quadratic function whose graph has vertex (−2,−1) and y-intercept 5.
Vertex form y = a (x+2)^2 -1 point given 0,5
5 = a(0+2)^2 -1 so a = 3/2
y = 3/2 (x+2)^2 -1 expand
y = 3/2 (x^2 +4x+4) - 1 simplify
3/2 x^2 +6x+5
