# Archive List for Secondary Math

## Midpoint Theorem and Similarity: Proofs, Converse, and Parallelogram Relationships

We will learn about similarity in mathematics. One of the important contents in the field of similarity is the midpoint theorem (or midpoint connector theorem). By using the midpoints of a triangle, we can calculate the side lengths. In addition to triangles, we can also calculate the side lengths of trapezoids and prove parallelograms. The […]

## Triangle Similarity in Math: Similarity Theorems, Proof and Similarity Ratio

A genre studied in mathematics is similarity. Similarity is frequently given as a problem in figures. In similarity problems, there are proof problems and calculation problems. Therefore, we need to learn the conditions under which figures are similar. Not only that, but you should be able to find the side lengths of similar figures. In […]

## Parallelogram Definition, Theorem (Property) and Proof Problems

One of the problems that is given in mathematics is proof. You have to prove that the figures of triangles are equal. In this case, parallelograms are often used in proofs. You will almost never be asked to prove that a shape is a parallelogram. On the other hand, problems that require you to prove […]

## Properties of Isosceles and Right Triangles: Congruence Theorems and Proof Problems

In mathematics, there are two types of shapes that we learn about: isosceles triangles and right triangles. The isosceles triangle and the right triangle are special triangles. Since they are special triangles, they have their own characteristics. By learning what characteristics they have, we will be able to calculate angles and prove shapes. Isosceles triangles […]

## Triangle Congruence Theorems: Proof Congruence Using SSS, SAS, ASA, AAS

The congruence condition of triangles is one of the shape problems we learn in mathematics. We learn when triangles have the exact same shape. After learning the triangle congruence theorems, students must learn how to prove the congruence. You will be asked to prove that two triangles are congruent. Many people are not good at […]

## Sum of Interior Angles and Exterior Angles of Polygons: Triangles, Quadrilaterals, and Pentagons

Many people know that the sum of the interior angles of a triangle is 180°. So why does the sum of the interior angles of a triangle equal 180°? Also, triangles are not the only shapes. There are quadrilaterals, pentagons, hexagons, and countless other shapes. These are called polygons. So, what is the sum of […]

## Vertical, Corresponding, and Alternate Angles: Why Angles are Equal and Proofs

In mathematics, we learn about plane shapes. One of the important topics is the vertical angle, corresponding angle, and alternate angle. These three angles are frequently encountered in problems involving figures. Therefore, it is a concept that you must understand. So, what are vertical angles, corresponding angles, and alternate angles? And what are their properties? […]

## The Basics of Solid of Revolution: Calculate the Volume and Surface Area

In mathematics, the problem of solid of revolution is sometimes presented. For a plane figure, we have to calculate the volume or surface area of the figure after one rotation. How to solve such a solid of revolution problem? For complex solid of revolution, we need to learn high school mathematics integration to be able […]

## Volume and Surface Area of the Sphere: Calculations in Mathematics Using Formulas

In mathematics, we calculate the volume and surface area of a sphere. We need to learn the formulas, and we can understand how to calculate the volume and surface area of a sphere by using the formulas. The formula that produces the volume and surface area of a sphere is a bit complicated. Also, to […]

## Volume and Surface Area of Pyramids and Cones: Formulas and Generatrix

In mathematical space figures, there is a problem to calculate the volume and surface area of a pyramid or cone. Unlike prisms and cylinders, how can we calculate the volume and surface area of a solid with a sharp pointed? Compared to prisms and cylinders, the calculation of pyramids and cones is more complicated. Especially […]