Question

Find the vertex AND factored form equation for both situations
1) A parabola has vertex (-1, 3) and goes through point (2, 5).
2) Write the equation for the parabola with x-intercepts (0, 1) and (0, -3) and stretched by a factor 4.

Answer 1

#1. Given the vertex, the equation is y = a(x+1)^2 + 3
now plug in the point to find a.

#2. Given the intercepts, we have
x = a(y-1)(y+3)
You don't say whether the stretch is horizontal or vertical.