Unit 4
Kenal Poligon Sekata
Di taman permainan, Lina nampak jubin lantai yang setiap satunya ada 6 sisi sama panjang.
Papan tanda BERHENTI pula ada 8 sisi sama panjang.
Bentuk-bentuk ini dipanggil poligon sekata.
正多边形 = poligon sekata
这一课认识正多边形。Lina 在游乐场看到地砖，每块都有 6 条一样长的边；红色的“停”字牌有 8 条一样长的边。像这样，每条边都是直的、而且全部一样长的平面图形，就叫正多边形。
例子：蜂巢的一个小格子就是有 6 条等长边的图形。
注意：边要全部一样长，只有几条一样长还不算。
regular polygon = poligon sekata
In this unit we meet regular polygons. At the playground Lina sees floor tiles that each have 6 equal sides, and the red STOP sign has 8 equal sides. A flat shape whose sides are all straight and all the same length is called a regular polygon.
Example: one small cell of a honeycomb is a shape with 6 equal sides.
Watch out: every side must be equal; having only a few equal sides is not enough.
Ciri-ciri
Apakah poligon sekata?
Sisi lurus · sama panjang · satu permukaan rata
segi tiga
sama sisi
sama sisi
segi empat
sama
sama
pentagon
heksagon
✓ sisi lurus ✓ semua sisi sama panjang ✓ tiada sisi melengkung
正多边形的特征 = ciri-ciri poligon sekata；直边 = sisi lurus
正多边形是平面（二维）图形，只有一个平面。它至少有 3 条边，每条边都是直线，而且全部一样长，没有弯的边。所以等边三角形和正方形也属于正多边形，五边形、六边形也一样。
例子：一块正方形的手帕，4 条边都一样长，就是正多边形。
注意：圆形没有直边，不是多边形。
features of a regular polygon = ciri-ciri poligon sekata; straight side = sisi lurus
A regular polygon is a flat, two-dimensional shape with one flat surface. It has at least 3 sides, every side is a straight line, and all the sides are the same length, with no curved edges. So an equilateral triangle and a square are regular polygons too.
Example: a square handkerchief has 4 equal sides, so it is a regular polygon.
Watch out: a circle has no straight sides, so it is not a polygon at all.
Lihat dan ukur
Lukis pentagon sekata
Setiap sisi diukur: semuanya 4 cm
5 sisi × 4 cm, sama panjang → pentagon sekata
量边长 = ukur panjang sisi；顶点 = bucu
动画一条一条画出五边形的边，每画一条就用尺量一次：第一条 4 cm，第二条也是 4 cm……五条边全是 4 cm，一样长。最后数顶点，也是 5 个。五条一样长的直边，所以它是正五边形。
例子：用 5 根一样长的冰棒棍首尾相接围起来，就能拼出正五边形。
注意：要每一条边都量过，才能说“全部一样长”。
measuring sides = ukur panjang sisi; vertex = bucu
The animation draws the pentagon one side at a time and measures each side with a ruler: the first is 4 cm, the second is also 4 cm, and all five sides are 4 cm. Then we count the corners and find 5 vertices. Five equal straight sides make a regular pentagon.
Example: five ice-cream sticks of the same length joined end to end make a regular pentagon.
Watch out: measure every side before saying they are all equal.
Cuba
Bentuk manakah poligon sekata?
选出正多边形 = pilih poligon sekata
A 是五边形，5 条直边一样长，是正多边形。B 是长方形，虽然边都是直的，但长边和短边不一样长，所以不是正多边形。C 有一条弯的边，根本不是多边形。
例子：正方形的四条边一样长，所以正方形是正多边形，长方形不是。
注意：很多同学以为长方形也是正多边形，要量一量长和宽。
choosing the regular polygon = pilih poligon sekata
A is a pentagon with 5 equal straight sides, so it is regular. B is a rectangle: its sides are straight, but the long sides and short sides differ, so it is not regular. C has a curved edge, so it is not a polygon at all.
Example: a square has four equal sides, so a square is regular but a rectangle is not.
Watch out: many pupils think a rectangle is regular; compare its length and width.
Nama poligon
Pentagon, heksagon, heptagon, oktagon
Nama ikut bilangan sisi
pentagon
5 sisi
5 sisi
heksagon
6 sisi
6 sisi
heptagon
7 sisi
7 sisi
oktagon
8 sisi
8 sisi
heksagon 6 · heptagon 7 — jangan keliru!
多边形名称 = nama poligon
正多边形按边数取名：5 条边叫 pentagon（五边形），6 条边叫 heksagon（六边形），7 条边叫 heptagon（七边形），8 条边叫 oktagon（八边形）。数边的时候，从一个顶点开始，用手指沿着边走一圈。
例子：“停”字交通牌有 8 条边，所以是 oktagon。
注意：heksagon 和 heptagon 读音很像，heksagon 是 6，heptagon 是 7。
names of polygons = nama poligon
Regular polygons are named by their number of sides: 5 sides is a pentagon, 6 sides is a hexagon (heksagon), 7 sides is a heptagon and 8 sides is an octagon (oktagon). To count the sides, start at one corner and trace all the way round with your finger.
Example: the STOP road sign has 8 sides, so it is an octagon.
Watch out: heksagon and heptagon sound alike; heksagon is 6 and heptagon is 7.
Cuba
Berapakah bilangan sisi sebuah heptagon?
七边形 = heptagon
heptagon 是有 7 条边的多边形。最容易跟 heksagon 搞混：heksagon 是 6 条边，heptagon 比它多一条，是 7 条。oktagon 才是 8 条边。可以把 heptagon 的 “t” 想成 tujuh（七）来记。
例子：一个正七边形的硬币形状，数一数正好有 7 条边。
注意：选 6 就是把 heptagon 当成了 heksagon。
heptagon = heptagon
A heptagon is a polygon with 7 sides. It is easy to confuse with the heksagon, which has 6 sides; the heptagon has one more, so 7. The oktagon is the one with 8 sides. Link the “t” in heptagon to tujuh, the Malay word for seven.
Example: a coin shaped like a regular heptagon has exactly 7 sides when you count them.
Watch out: choosing 6 means you mixed up heptagon and heksagon.
Sisi dan bucu
Bilangan sisi = bilangan bucu
Setiap bucu ialah tempat dua sisi bertemu
heksagon
| Poligon | sisi | bucu |
|---|---|---|
| pentagon | 5 | 5 |
| heksagon | 6 | 6 |
| heptagon | 7 | 7 |
| oktagon | 8 | 8 |
边数等于顶点数 = bilangan sisi sama dengan bilangan bucu
顶点是两条边相接的地方。数六边形：红点是顶点，一共 6 个；边也是 6 条。因为每走过一条边就到达一个新的顶点，走一圈回到起点，边和顶点的数目一定一样。表格里五边形到八边形都是这样。
例子：八边形有 8 条边，所以也有 8 个顶点。
注意：数顶点时把起点做个记号，免得数两次。
sides equal vertices = bilangan sisi sama dengan bilangan bucu
A vertex is where two sides meet. On the hexagon the red dots are the vertices, 6 of them, and there are also 6 sides. Each side you walk along brings you to a new corner, so after one full lap the number of sides and vertices must match. The table shows this for pentagon to octagon.
Example: an octagon has 8 sides, so it also has 8 vertices.
Watch out: mark your starting corner so you do not count it twice.
Cuba
Sebuah poligon sekata ada 8 bucu. Apakah namanya?
由顶点推名称 = cari nama daripada bucu
正多边形的边数等于顶点数。有 8 个顶点，就有 8 条边。8 条边的多边形叫 oktagon（八边形）。heptagon 是 7 条边，heksagon 是 6 条边，都不对。
例子：一个多边形有 5 个顶点 → 5 条边 → pentagon。
注意：先把顶点数换成边数，再对名字。
from vertices to name = cari nama daripada bucu
A regular polygon has as many sides as vertices. With 8 vertices it has 8 sides, and a polygon with 8 sides is an octagon (oktagon). A heptagon has 7 sides and a heksagon has 6, so neither fits.
Example: a polygon with 5 vertices has 5 sides, so it is a pentagon.
Watch out: change the number of vertices into the number of sides first, then match the name.
Awas!
Bukan poligon sekata
Sisi tidak sama panjang, atau ada sisi melengkung
segi empat tepat
sisi tidak sama
sisi tidak sama
heksagon
sisi tidak sama
sisi tidak sama
separuh bulatan
ada sisi melengkung
ada sisi melengkung
✗ Bukan poligon sekata
不是正多边形 = bukan poligon sekata
长方形有 4 条直边，但长边和短边不一样长，所以不是正多边形。右边的六边形虽然有 6 条边，可是上下两条特别长，也不是正多边形，只能叫普通的六边形。半圆有一条弯边，连多边形都不是。
例子：一张 A4 纸是长方形，不是正多边形；一张方形折纸才是。
注意：边数对了还要检查每条边是不是一样长。
not a regular polygon = bukan poligon sekata
A rectangle has 4 straight sides, but the long and short sides differ, so it is not regular. The hexagon in the middle has 6 sides, yet the top and bottom sides are much longer, so it is only an ordinary hexagon, not a regular one. A semicircle has a curved edge, so it is not even a polygon.
Example: an A4 sheet is a rectangle, not a regular polygon; a square origami sheet is.
Watch out: even with the right number of sides, check that every side is the same length.
Cuba
Mengapakah bentuk ini bukan poligon sekata?
找原因 = cari sebab
这个图形有 6 条边、6 个顶点，每条边也都是直的。但是上面和下面两条边比斜的四条边长得多，边不一样长，所以它不是正六边形，只是普通六边形。
例子：拉长了的蜂巢格子，边就不再一样长了。
注意：没有弯边、顶点数也对，并不代表就是正多边形。
finding the reason = cari sebab
This shape has 6 sides and 6 vertices, and every side is straight. But the top and bottom sides are much longer than the four slanted sides, so the sides are not all equal. It is an ordinary hexagon, not a regular one.
Example: a stretched honeycomb cell no longer has equal sides.
Watch out: having no curved edges and the right number of vertices does not make a shape regular.
Padankan
Poligon dan namanya
配对名称 = padankan nama
先数每个图形的边：5 条是 pentagon，6 条是 heksagon，7 条是 heptagon，8 条是 oktagon。图形越多边，看起来越像圆，所以七边形和八边形要慢慢数，别看一眼就猜。
例子：数出 6 条边 → 选 heksagon。
注意：数的时候用手指点着每条边，数完一圈就停。
matching names = padankan nama
Count the sides of each shape first: 5 is a pentagon, 6 a heksagon, 7 a heptagon and 8 an oktagon. The more sides a shape has, the more it looks like a circle, so count the heptagon and octagon carefully instead of guessing at a glance.
Example: 6 sides counted means you pick heksagon.
Watch out: point at each side as you count and stop after one full lap.
Ringkasan
Syabas!
sisi lurus · sama panjang · sisi = bucu
Poligon sekata: semua sisi lurus dan sama panjang. Pentagon 5, heksagon 6, heptagon 7, oktagon 8. Bilangan sisi sama dengan bilangan bucu. Segi empat tepat bukan poligon sekata.
Latihan tambahan →