Asked by Kells
What is "vertex (2,1), point (1, -5)" in vertex form?
Answers
Answered by
Kells
Also could someone show me how to write it in vertex form, please?
Answered by
mathhelper
If the vertex is (h, k), then the form of the equation you want is
y = a(x - h)^2 + k , so for your information with a vertex of (2,1) you have
y = a(x - 2)^2 + 1
so the only missing part is the value of a
but you also know that the point (1, -5) lies on your parabola, so ....
-5 = a(1-2)^2 + 1
-6 = -a
a = 6
equation : y = 6(x - 2)^2 + 1
y = a(x - h)^2 + k , so for your information with a vertex of (2,1) you have
y = a(x - 2)^2 + 1
so the only missing part is the value of a
but you also know that the point (1, -5) lies on your parabola, so ....
-5 = a(1-2)^2 + 1
-6 = -a
a = 6
equation : y = 6(x - 2)^2 + 1
Answered by
correction - mathhelper
that should have been
a = -6
and
y = -6(x - 2)^2 + 1
a = -6
and
y = -6(x - 2)^2 + 1