Viewing in Doors & Windows. Many people use a screwdriver to remove a hinge pin when taking off a door. They simply place the tip up under the head of the pin and then tap on the end with a hammer.
Complementary angles are two angles whose measures add up to 90 degrees. You can think of them as two puzzle pieces that form one 90 degree angle when they are put together. When talking about complementary angles, it's important to remember that they're always in a pair.
1 If the two complementary angles are adjacent their non-shared sides form a right angle. 2  In Euclidean geometry, the two acute angles in a right triangle are complementary, because the sum of internal angles of a triangle is 180 degrees, and the right angle itself accounts for ninety degrees.