Suppose a circle with center (1, −3) passes through point (1, −1). Which equation represents the circle?

It is C)  (x − 1)^2 + (y + 3)^2 = 4

Step-by-step explanation:

The radius is the distance between the center and the point on the circle.

Center: (1, −3); Point: (1, −1)

Distance formula: d =  square root of {(x2 - x1)^2 + (y2 - y1)^2}

r = square root of  {(1 − 1)^2 + (−1 + 3)^2 }

r =  square root of {0 + 4 } = 2

(x − h)^2 + (y − k)^2 = r2 > (x − 1)^2 + (y + 3)^2 = 4

Hope this isn't confusing and helps. I also know its right because I just did this on USA Testprep.

1) c 2143.6 cm

2) c 113.0 m

3) a 33.5 ft

4)   d 2 cm

5) c 20 mm

6) 180 in

7) d 120 ft

24

step-by-step explanation:

the graph shows 30% of students walk. 80 students were questioned, so the number that said they walk is

30% × 80 = 0.30 × 80 = 24