This question is lacking vital information, such as when they got there.
The other person is literally wrong. The answer is D. Supplementary because two angles that add up to 180 are supplementary angles.
Since only one person can finish in first place, one in second, etc., the total number of placers is 12x11x10, or 1320 different ways the 12 racers can finish 1st, 2nd and 3rd....
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Answer:
Presumably you're solving for x here? Without further information we'll assume that.
With that in mind, x is approximately equal to 0.86 and -0.46
Step-by-step explanation:
Let's start by putting it in the usual ax² + bx + c format.

let's solve it. First we'll multiply both sides by five, making the first term a perfect square:

Now we'll add 11 to both sides:

Which makes the left side a perfect square:

And now we can solve for x:

Note that there's no apparent way of drawing the ± symbol when editing equations, so take that + sign as actually being ±.
That gives us two answers:

The rotational symmetry has more than one order of rotational symmetry the objects can fit itself within 360 degrees.