If your directrix is a "y=" line, that means that the parabola opens either upwards or downwards (as opposed to the left or the right). Because it is in the character of a parabola to "hug" the focus, our parabola opens upwards. The vertex of a parabola sits exactly halfway between the directrix and the focus. Since our directrix is at y = -2 and the focus is at (1, 6) AND the parabola opens upward, the vertex is going to sit on the main transversal, which is also the "line" the focus sits on. The focus is on the line x = 1, so the vertex will also have that x coordinate. Halfway between the y points of the directrix and the focus, -2 and 6, respectively, is the y value of 2. So the vertex sits at (1, 2). The formula for this type of parabola is where h and k are the coordinates of the vertex and p is the DISTANCE that the focus is from the vertex. Our focus is 4 units from the vertex, so p = 4. Filling in our h, k, and p: . Simplifying a bit gives us . We can begin to isolate the y by dividing both sides by 16 to get . Then we can add 2 to both sides to get the final equation , choice 4 from above.
60cm2 !! enjoy your day !!
The Golden Ratio is a mathematical relationship that exists
in art, shapes, nature and the human body. The golden ratio can be present in
your body, from the length of your arms and legs when compared to your torso.
Fingers is another example because the length of our fingers, each section from
the tip of the base to the wrist is larger than the preceding.
The measurement of the human navel to the floor and to the
top of the head to the navel is also the Golden ratio. Plastic surgeons and
dental surgeons use it to reconstruct the human face. It also appears in everything
around us like in the nature and science. It appears on in flower petals
because it is believed that each petal is placed to so that each petal gets the
best exposure to sunlight. Dolphins, starfish, sea urchins and honeybees also
exhibit the proportion like humans. DNA molecules measures 34 angstroms by 21
angstroms at each full cycle of the double helix spiral, these two number are
successive numbers. I think that the Golden Ratio is just a freak coincidence
that happened.
Mel purchased 5 shirts and Joe purchased 2 shirts.
Answer:
Three plus 6=9 times 11=99+1=100-4=96 divided by 8=12 times 2= 24