Answer:
<h2>
50°, 60°, 70° (the second answer)</h2>
Step-by-step explanation:
The sum of the angles in a triangle = 180°
We can use the equation:
2x + 80 + 25 - 5x + 6x + 90 = 180
Combine like-terms:
2x + 6x - 5x = 3x
80 + 25 + 90 = 195
195 + 3x = 180
Subtract 195 from both sides:
3x = -15
Divide both sides by -3 to isolate x:
x = -5
Now that you've solved for x, you can replace x with -5 in the equation for each angle.
2(-5) + 80 = 70°
6(-5) + 90 = 60°
25 - 5(-5) = 50°
60°, 120° and 180° are the angles at which it will map onto itself.
Essentially, we just use the pythagorean theorem to solve:
7^2 + 3^2 = c^2
49 + 9 = c^2
58 = c^2
c = sqrt 58
The answer is Option D.
2.15 would be your answer