Length of circular track is:

L = 2*r*pi

He run 3/4 of it so length is:
L' = 3*2/4*r*pi = 3/2*r*pi

To calculate speed of his movement we use formula:
v = s/t where s = L' and t = 1 minute 45 seconds = 105 seconds

v = L'/t = 3*r*pi/2*105

v = r* pi/70

If we take that r = 1

answer
$\pi /70$

6 0

2 years ago

Which is the focus of a parabola with equation y2 = 4x?

statuscvo [17]

Answer:

(1, 0)

Step-by-step explanation:

Please write this as y^2 = 4x; the " ^ " indicates exponentiation.

The appropriate equation for a horizontal parabola that opens to the right is

y^2 = 4px

Here, we are told that y^2 = 4x; this tells us that 4p = 4, and so p = 1.

Again, this parabola is a horizontal one and it opens to the right. p = 1 is the distance of the focus from the vertex, and in this case p = 1. Thus, the focus is at (1, 0) (situated on the x-axis).

6 0

2 years ago