When a cube is intersected by a plane parallel to its base, a square is created. A rectangle is created when a cube is intersected by a plane in 2 pairs of opposite faces. When a cube is intersected by a plane in 3 adjacent faces, a triangle is formed.
Since a cube does not have any curved faces, so a plane will not be able to intersect it and give a cross section with any curves.
Triangle EDF is a right triangle and we know that angle 1 is equal to 53 degrees. So, angle 2 is equal to 180-90-53 = 37 degrees. Now that we want to find angle 3, we subtract the measure of angle 2 (which is 37) from 180. That gives us 143 degrees.
