We know how we got 90, since a right angle is 90 degrees,
180 degrees are in a triangle.
180-90=90
Find the pair that equals 90 so you get 180 degrees!
If you have more questions don’t have hesitation to ask!
Or add all number to get 180 degrees!
<-------------.-------------->
0 1 2 3 4 5 6 7 8 9 10
The answer would be
or 27.7 km²
if rounded to the nearest tenth
