Question

Which of the following equations is of a parabola with a vertex at (0, -5)?

y = (x - 5)^2
y = (x + 5)^2
y = x^2 - 5
y = x^2 + 5

Thank you

Answer 1

The equation of a parabola with Vertex V=(h,k) is
y=a(x-h)^2+k
If the Vertex is V=(0,-5)=(h,k)→h=0, k=-5
Replacing h=0 and k=-5 in the equation above:
y=a(x-0)^2+(-5)
y=ax^2-5

Answer: Third option: y=x^2-5