## Obtuse Angles

An Obtuse Angle is more than 90° but less than 180° Examples More Examples of obtuse angles Which is Obtuse Angle? Remember to look carefully at which angle you are being asked to name. The obtuse angle is the smaller angle. It is more than 90° and less than 180°. The larger angle is a

## Consecutive Interior Angles

Definitions When two lines are crossed by another line (Transversal), Consecutive Interior Angles are the pairs of angles on one side of the transversal, but inside the two lines. The 2 angles in purple (d and e) make one pair of consecutive interior angles, and the other 2 angles in red (c and f) make another

## Square: Definition, Area, Perimeter, Diagonal, & Examples

Square is one of common things in daily life. There are many square things. They are chess board, clock, crackers, origami paper, etc.. Definition of Square Square is specific shape of rectangle. It is because square has right angles in all of the corner. But it has same length in all of the sides. Besides

## Plane Geometry Examples

1. Johny walked in a garden start from point A. Then he walk to the west 14 meters to point B and he turn to the north 48 meters. The last position was named as C. If he want to go to C shortly, how far the distance? 2. Look at the figure Determine the

## Parallel Lines

Lines are parallel if they are always the same distance apart (called “equidistant“), and will never meet. Definition of Parallel Lines Parallel lines in geometry are lines in a plane which do not meet. They don’t intersect each other at any point. By extension, a line & a plane, or 2 planes, in 3D Euclidean

## Rectangle: Definition, Area, Perimeter, Diagonal, Properties, & Examples

One type of shape in geometry is rectangle. There are many rectangle-shape things in daily life for example table, whiteboard, books, phone, door, window, etc. Definition of Rectangle Rectangle is one of a two-dimensional shape in geometry. It has two (pairs) parallel sides that they are two lengths and two widths. The length and width

## Angles

Definition An angle measures the amount of turn Names of Angles As the Angle Increases, the Name Changes: Type of Angle Description Illustration Acute Angle is less than 90°   Right Angle is 90° exactly         Obtuse Angle is greater than 90° butless than 180°    Straight Angle is 180° exactly   Reflex Angle is

## Cone: Definition, Properties, Types, Surface Area, Volume

Have you ever eaten ice cream? One of the shapes is cone. Besides that, other cone things are traffic cone, cone snail, party hat, megaphone, etc.. Definition of Cone Cone is a three-dimensional shape that has a flat base, a curved surface, and a point in the top (apex). The flat base is circular shape

## Circle: Definition, Parts, Area, Perimeter, Examples

Circle is one of familiar shape in daily life. It was studied since long time ago. There are many things that is circle such as clock,  wheel, gear, ring, coins, etc.. Definition of Circle Circle is two-dimensional shape. It is set of points that has same distane from the center in a plane. In another words, there are

## Trapezoid: Definition, Kinds, Area & Perimeter Formula, Examples

Geometry is one of mathematics’ branch. It has many shapes that one of them is plane geometry. In plane geometry, there is quadrilateral shape that has many kinds of it. One of them is trapezoid. In daily life, trapezoid can be found in handbag, bridges, and popcorn box in cinema. Definition of Trapezoid Trapezoid is