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
D. 2(n-8)
The difference of a number and eight is separate from being multiplied by 2 which is why you would use parenthesis.
I think its B because, the formation would be (x,y) so that means (5,-3)
ANSWER:
The surface area of the star is 3.2700 x
square kilometres.
EXPLANATIONS:
Diameter of the star = 1.8083 x
Km.
Surface area of the star = 4
Where n is the radius of the star.
So that;
n =
= 0.90415 x 
n = 0.90415 x
Km
Thus,
Surface area = 4 x 
= 326994889
Surface area = 3.2700 x

Therefore, the surface area of the star is 3.2700 x
square kilometres.