How can the equation of a parabola be derived when given the focus and the directrix?

1 answer:

4 0

The distance between any point (x0,y0) on the parabola and the focus (m,n) is the same as the distance between (x0,y0) and the directrix line ax+by+c. The distance between (x0,y0) and focus (a,b) is \sqrt((x-m)^2+(y-n)^2). The distance between (x0,y0) and ax+by+c is |ax0+by0+c|/\sqrt(m^2+n^2). Equalize these two expressions.

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a city that has an elevation of 15 meters is closer to sea level than a city with an elevation of -10 true or false? explain you

12345 [234]

Answer:

False

Step-by-step explanation:

At sea level, elevation is 0. This means that we can portray sea level as being the midpoint of distances below sea level and distances above sea level.

Thus, a distance of 1 m below sea level = - 1 is equivalent to a distance of 1 m above sea level albeit in opposite directions.

Hence, an elevation of 15m above sea level is greater in distance Than an elevation of - 10 m below sea level because the absolute value of 15 is greater than the absolute value of 10.

|15 - 0|= 15

|-10 - 0| = 10

Hence, elevation of - 10 below Sea level is closer to sea level than elevation of 15 above sea level

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Tan x + pi / 6 what is this equal to?

Scilla [17]

If tan (x)+pi/6=0

thn

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take atan of both sides

x=atan (-pi/6)
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3 years ago

Two sisters share a lottery win of $1,400,000. If

Sedaia [141]

Answer:

$600,000:$800,000

Step-by-step explanation:

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2 years ago

What is the sum of the geometric series in which a1 = −5, r = 3, and an = −405?

xxMikexx [17]

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artcher [175]

Okay so 11/4 needs to be multiplied by 2 so that the D match up.

so 11/4 x 2 = 22/8

22/8 - 3/8 = 19/8

The difference is 19/8

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3 years ago