Sut i adnabod polygonau

Ffocws dysgu

Dysga ddefnyddio sgiliau geometreg i adnabod a chategoreiddio trionglau, sgwariau, petryalau, pentagonau a hecsagonau, gan gynnwys siapiau afreolaidd.

Mae'r wers hon yn cynnwys:

• un fideo
• un gweithgaredd

Learning focus

Learn to use geometry skills to recognise and classify triangles, squares, rectangles, pentagons and hexagons, including irregularcases.

This lesson includes:

• one video
• one activity

Fideo / Video

Dewch i gwrdd a chymharu'r siapiau gwahanol ym mharti'r polygonau.

Come and meet and compare the different shapes in the polygons' party.

Nodiadau i rieni

• Polygon yw siâp dau ddimensiwn gydag ochrau syth.
• Mae polygonau yn gallu cael eu grwpio o ran faint o ochrau sydd gyda nhw.
• Mae polygon gyda 4 ochr yn cael ei alw’n pedrochr. Mae’r onglau mewnol yn adio i wneud 360 gradd. Mae’r sgwâr, petryal, rhombws a pharalelogram, barcud a thrapesiwm yn enghreifftiau o bedrochr.
• Mae polygon gyda 3 ochr yn cael ei alw’n triongl. Mae’r onglau mewnol yn adio i wneud 180 gradd.
• Mae triongl isosgeles, triongl anghyfochrog, triongl hafalochrog a thriongl ongl sgwâr yn enghreifftiau o drionglau.
• Mae polygonau sydd ag ochrau o wahanol hyd ac onglau gwahanol yn cael eu galw’n polygonau afreolaidd.
• Dydy cylch ddim yn bolygon oherwydd does dim ochrau syth ganddo.
• Mae pentagon, hecsagon, heptagon ac octagon hefyd yn enghreifftiau o bolygonau.

Notes for parents

• *A polygon is a two dimensional shape with straight sides. *
• *Polygons can be grouped according to the number of sides they have. *
• *A polygon with 4 sides is called a quadrilateral. Their inner angles make a total of 360 degrees. A square, rectangle, rhombus, parallelogram, kite and trapezium are all examples of quadrilaterals. *
• *A polygon with 3 sides is called a triangle. Their inner angles make a total of 180 degrees. *
• *The isosceles triangle, scalene triangle, equilateral triangle and a right-angled triangle are all examples of these. *
• *Polygons with lengths of different sizes and angles are called irregular polygons. *
• *A circle is not a polygon because it does not have straight sides. *
• *A pentagon, hexagon, heptagon and octagon are all examples of polygons. *

Parti’r polygonau

Dim ond siapiau 2D gydag ochrau syth sydd wedi’u gwahodd i barti’r polygonau.

Pedrochrau

Mae gan bedrochrau 4 ochr ac mae eu honglau mewnol yn adio i 360°.

Mae sgwâr, petryal, rhombws, paralelogram, barcud a thrapesiwm i gyd yn bedrochrau.

Trionglau

Mae gan drionglau 3 ochr. Mae eu honglau mewnol yn adio i 180°.

Dyma’r mathau o driongl sydd:

• isosgeles
• hafalochrog
• anghyfochrog
• ongl sgwâr

Polygonau afreolaidd

Mae gan bolygonau afreolaidd ochrau o wahanol hyd a gwahanol onglau.

Polygonau rheolaidd

Mae enwau gan siapiau eraill sydd ag ochrau o’r un hyd.

Mae’r rhain yn cynnwys:

• pentagon, sydd â 5 ochr
• hecsagon, sydd â 6 ochr
• heptagon, sydd â 7 ochr
• octagon, sydd ag 8 ochr

Mae’r siapiau hyn i gyd yn wahanol, ond polygonau ydyn nhw i gyd.

The polygons' party

Only 2D shapes with straight sides are invited to the polygon party.

Quadrilaterals

Quadrilaterals have 4 sides and their internal angles add up to 360°.

A square, rectangle, rhombus, parallelogram, kite and trapezium are all quadrilaterals.

Triangles

Triangles have 3 sides. Their internal angles add up to 180°.

The types of triangle are:

• isosceles
• equilateral
• scalene
• right-angled

Irregular polygons

Irregular polygons have sides of different lengths and angles.

Regular polygons

There are names for other shapes with sides of the same length.These include:

• pentagon, which has 5 sides
• hexagon, which has 6 sides
• heptagon, which has 7 sides
• octagon, which has 8 sides

All these shapes are different, but they are all polygons.

Gweithgaredd / Activity

Dewisa’r siâp sy’n ateb y disgrifiad: trapesiwm - triongl - petryal

Select the shape that fits the description:trapesiwm (trapezium) - triongl (triangle) - petryal (rectangle)