Triangles are the building blocks of all other straight-edged shapes. They were used for hundreds of years to create accurate maps and GPS today still works using trigonometry. Even the pixels on phones and screens use trigonometry.We...

The area of a triangle is ½ the base X perpendicular height. If we don’t have the perpendicular height, there is another formula we can use: 1/2absinC which we look at in this video. We need two sides and the angle in between. This will...

Circle Theorems part 2/3: The teacher in the video explains and proves 9 out of 12 theorems related to circles, using basic concepts and properties of triangles. The theorems include equal chords of a circle, angles subtended by an arc...

This video explains about Basic Proportionality Theorem with the help of an activity .

Not every triangle is a right-angle triangle, so we can't always use Pythagoras and SOHCAHTOA to find missing sides and missing angles. We instead use the sine rule or the cosine rule. They can both be used to find either missing sides...

👉 Learn about the points on the unit circle. A unit circle is a circle which radius is 1 and is centered at the origin in the cartesian coordinate system. To construct the unit circle we take note of the points where the unit circle...

Law of Cosines

SchoolOnline's Secondary Maths videos are brilliant, bite-size tutorial videos delivered by examiners. Ideal for ages 13-17, they cover every key topic and sub topic covered in GCSE Maths in clear and easy to follow steps. This video...

SchoolOnline's Secondary Maths videos are brilliant, bite-size tutorial videos delivered by examiners. Ideal for ages 13-17, they cover every key topic and sub topic covered in GCSE Maths in clear and easy to follow steps. This video...

SchoolOnline's Primary Maths videos are brilliant, bite-size tutorial videos delivered by examiners. Ideal for ages 9-13, they cover every key topic and sub topic covered in Maths in clear and easy to follow steps. This video looks at...

The Sine This video is a lecture on the sine rule in trigonometry, focusing on how to use it to solve problems involving non-right-angled triangles. The video begins with an overview of trigonometry and the important ratios sine, cosine,...

SchoolOnline's Secondary Maths videos are brilliant, bite-size tutorial videos delivered by examiners. Ideal for ages 13-17, they cover every key topic and sub topic covered in GCSE Maths in clear and easy to follow steps. This video...

👉 Learn how to solve with the ratio of sides and angles of a triangle. Given the ratio of the sides of a triangle and the perimeter of the triangle, we can solve for the actual lengths of the triangle. Similarly, when the ratio of the...

👉 Learn how to solve word problems with triangles. A word problem is a real-life situation which can be modelled mathematically. Word problems involving angles of elevation and depression, straight object leaning against a vertical...

Doritos history? I'll have a bag...Weird History Food is going to get your fingers nice and sticky red on this one because we're talking all about the history of one of the most beloved chips: Doritos. Weird History Food will take you...

In this video, a teacher explains how the midpoint theorem in geometry can be applied in real-life situations, using the example of hanging an LED light at the center of a building. The teacher breaks down the steps to prove the theorem...

In this video we will learn basic patterns in mandala using lines, petals, triangle, and circles.

👉 Learn how to solve word problems with triangles. A word problem is a real-life situation which can be modelled mathematically. Word problems involving angles of elevation and depression, straight object leaning against a vertical...

The video explains the basics of trigonometry, the three important ratios (sine, cosine, and tangent) used to calculate side lengths and angles in triangles, and the labeling of right angle triangles. It then focuses on the cosine...

The video is a lecture presentation on the concept of angle sums in triangles. The video then demonstrates how this property can be used to calculate missing angles in a triangle by finding what is already known and subtracting it from...

In this video, the topic of "proof by deduction" is discussed. The concept of logical consequence is introduced and explained, and various examples are provided to demonstrate how to use proof by deduction to prove mathematical...

👉 Learn the essential definitions of triangles. A triangle is a polygon with three sides. Triangles are classified on the basis of their angles or on the basis of their side lengths. The classification of triangles on the bases of their...

👉 Learn how to determine whether two triangles are similar given the coordinate points of the vertices of the triangle. Two triangles are said to be equal when the corresponding angles of the triangles are congruent (equal) or when the...

SchoolOnline's Secondary Maths videos are brilliant, bite-size tutorial videos delivered by examiners. Ideal for ages 13-17, they cover every key topic and sub topic covered in GCSE Maths in clear and easy to follow steps. This video...