Answer: Stratified
Step-by-step explanation:
Pretty much and in short, make up your own measure.
so... say you can use a tie or something with length, and use that to measure whatever object you need it for.
for example, I can just grab a string, cut it, and measure something, and the measurement may just be that the object is my string 6 times, so I know the length of the object is 6 times the length of the string I cut.
it doesn't quite matter how long the string cut was, all that matters is that is relable or referenciable for reuse. Later on I could always just get the string measure and convert it to metric, once I found a ruler or imperial units.
but in the short run, it doesn't really matter the length of the string cut, all that matters is that is referenciable, the object will be 6 times my string cut, here, in France, in Pluto, in Andromeda, anywhere.
bear in mind that the measure units we use today, are only usable because they're referenciable, so if I tell you 15 inches of something, you know how much 15 inches is, so that's all that matters.
Answer:
y = -1/8(x -1)² +4
Step-by-step explanation:
The equation of a parabola can be written from focus and directrix using the form ...
y = 1/(4p)(x -h)² +k
where p is the distance from vertex to focus, and (h, k) is the vertex.
The vertex-focus distance is half the distance from the directrix to the focus. Here, that is ...
p = (2 -6)/2 = -4/2 = -2
The vertex is halfway between the focus and directrix on the same vertical line, so has coordinates ...
(h, k) = ((1, 2) +(1, 6))/2 = (1, 4)
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Using these values of p and (h, k), we find the equation of the parabola to be ...
y = 1/(4(-2))(x -1)² +4
y = -1/8(x -1)² +4
_____
<em>Additional comment</em>
You can check the graph by considering the definition of a parabola: each point on the curve is equidistant from the focus and the directrix. This is easily verified for points on the horizontal and vertical lines through the focus. For example, point (5, 2) is 4 units from the focus, and 4 units from the directrix.
I tried, but I kept getting 7542...which isn't an answer choice.