Answer:
Step-by-step explanation:
Given: The radius of circle O is r, and the radius of circle X is r'.
To prove: Circle O is similar to circle X.
Proof: Move the center of the smaller circle onto the center of the largest circle. Translate the circle X by the vector XA onto circle O. The circles now have the same center.
A dilation is needed to increase the size of circle X to coincide with the circle O. A value which when multiplied by r' will create r.
The scale factor x to increase X:
⇒
A translation followed by a dilation with scale factor will map one circle to the other, thus proving the given both circles similar.
Therefore, circle O is similar to circle X.
Step-by-step explanation:
You do 4 x 56 = 224. It’s just multiplication.
Answer:
Since the focus is at (-6,-11) and the directrix is at y=9:
The vertex is halfway between the focus and the directrix, so the vertex is at (-6,-1). (Draw this on graph paper if that doesn't make sense.)
The general form (conics form) of a parabola: 4p(y-k)=(x-h)^2 (vertex is (h,k) and "p" is the distance between the focus and vertex (or between vertex and directrix)).
(h,k) = (-6,-1)
p = 10 (distance between focus and vertex), so 4p = 40.
Therefore:
40(y+1)=(x+6)^2
Or if you need to rearrange to "vertex form": y=(1/40)(x+6)^2 - 1
Step-by-step explanation:
One important feature of the parabola is that it has an extreme point, called the vertex. If the parabola opens up, the vertex represents the lowest point on the graph, or the minimum value of the quadratic function.
<span>for example, (1;5)
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