20. square-10+10=20x2=400m^2
circle- 3.14x10^2=3.14x100=314
400-314=86
86m^2
21.i don't get 21 sorry
A polygon<span> has as many interior </span>angles<span> as sides. An equilateral triangle has three equal 60 </span>degree angles<span>. The </span>sum<span> of the </span>angles<span> of this and any triangle is </span>180 degrees<span>.The </span>sum<span> of the four interior </span>angles<span> of a square is 360 </span>degrees<span>, which is the same for any quadrilateral.</span>
So the figure is called a ray. Which is when there’s a point and than an arrow extends off that point forever. But the way to write a ray is by putting an arrow above it.
Sixty square root five (simplified) There ya go hope it helps
