Circumference=2πr
=2*3.14*105
=659.4cm
NOT NECESSARILY would a triangle be equilateral if one of its angles is 60 degrees. To be an equilateral triangle (a triangle in which all 3 sides have the same length), all 3 angles of the triangle would have to be 60°-angles; however, the triangle could be a 30°-60°-90° right triangle in which the side opposite the 30 degree angle is one-half as long as the hypotenuse, and the length of the side opposite the 60 degree angle is √3/2 as long as the hypotenuse. Another of possibly many examples would be a triangle with angles of 60°, 40°, and 80° which has opposite sides of lengths 2, 1.4845 (rounded to 4 decimal places), and 2.2743 (rounded to 4 decimal places), respectively, the last two of which were determined by using the Law of Sines: "In any triangle ABC, having sides of length a, b, and c, the following relationships are true: a/sin A = b/sin B = c/sin C."¹
A: 100 cm³
This is because the others can be multiplied by something 3 times to get it, but A can not.
Since A‘(-1,1) is on the line y=-x, reflecting it about the line doesn't change its coordinate, so A's coordinate is (-1,1). Reflecting B'(-2,1) about y=-x switches both the sign and the number of x and y, so B=(-1,2), and C'(-1,0) becomes C(0,1). Drawing out the graph with the points and the line helps.
Well 22/7 is 3.14 and so on but since there is a little more than 3 you need to make sure he covers up all the fencing places... SO John will need 4 fences