# Hatsudy

## Triangle Congruence Theorems: SSS, SAS, ASA, and AAS

The congruence condition of triangles is one of the geometry problems we learn in mathematics. We learn under what conditions two triangles can have exactly the same shape. After learning the triangle congruence theorems, we need to learn how to prove the congruence. You will be asked to prove that two triangles are congruent. Many […]

## 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 a Solid of Revolution: Calculate the Volume and Surface Area

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

## The volume and Surface Area of a Sphere: Calculations in Math 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 in calculating the volume and surface area of a pyramid or cone. Unlike prisms and cylinders, how can we calculate the volume and surface area of an object with a sharp-pointed? Compared to prisms and cylinders, the calculation of pyramids and cones is more complicated. Especially when […]

## Surface Area of Prisms and Cylinders: Calculations and Formulas

In mathematics, we learn about space figures. We learn the area and volume of a three-dimensional figure, not a plane. One such field is the surface area of prisms and cylinders. How can we calculate the surface area of prisms and cylinders? When calculating the surface area of a prism or cylinder, the method of […]

## The Arc Length and the Sector Area: Circles and Arcs in Math

In mathematics, we sometimes calculate the length of the arc and the area of a sector. How do we calculate an arc length and a sector area? When calculating the arc length and the sector area, we must understand the properties of a circle. If we can calculate the length of the circumference and the […]

## Basics of Math Probability: Coins and Dice with a Tree Diagram

In mathematics, we study probability. Probability is so familiar in our lives and all statistics are based on probability. If you learn probability, you will be able to understand what is going on in the news. Also, experimental data in science is processed using probability. Whether or not it will rain in a weather forecast […]

## Basics of Quadratic Functions: How to Solve Problems and Draw Graphs

In mathematics, we learn about quadratic functions. A graph that has a square and is a quadratic function, and a graph has a curve. In mathematics involving graphs, we first learn direct proportions. The graphs that apply direct proportions are linear functions. Further advancement of linear functions is quadratic functions. The concept of linear and […]