First you have to figure out the length of the track:

r is the half of the diameter:
200ft : 2 = 100ft

= 200

≈
628,31
The athlete has to run ca. 5280ft for one mile:
5280 : 628,31≈8,4
The athlete has to run 8,4 laps
Answer:
C, (x = 100, y = 10)
Step-by-step explanation:
hi again,
(2x - 70) = (x + 30), by the Alternate Exterior Angles
x - 70 = 30
<em>x = 100</em>
<em />
(2x - 70) + 5y = 180, by the Linear Pair Theorem
2(100) - 70 + 5y = 180
200 - 70 + 5y = 180
130 + 5y = 180
5y = 50
<em>y = 10</em>
The first x is the horizontal coodinate (abscisa) and second is the vertical coordinate (ordenate). Both are coordinates. (x,y) has the meaning of a complex number: x is the real part and y is the imaginary part: x+yi. (x,y) has the meaning of a plane's vector from origin of coordinates.