Lewis structure. The Lewis structures, also called Lewis-dot diagrams or electron dot diagrams are pictures that show the bonding between a pair of electrons and the atoms of a molecule. Each dot represents one electron. Two dots side by side represent a lone pair of electrons.
Right angles are like corners and measure 90Â°. Acute angles are smaller than 90Â°. Obtuse angles are larger than 90Â°, but less than 180Â°. And straight angles are 180Â°, which is where the two lines go in the same direction and become like a single straight line. And that's all there is to it: each of the four types of angles in mathematics.
Some triangles will have one angle that is exactly 90 degrees. Those are right triangles because one angle is 90 degrees. (The other two angles must be acute because they must add up to 90 degrees.) Some triangles will have one angle that is more than 90 degrees. Those are obtuse triangles because one angle is obtuse. (The other two angles are acute because the sum of the other two triangles is less than 90 degrees). Some triangles will have all three angles less than 90 degrees. Those are the acute triangles. Go ahead, start with a right triangle.