Cabar Minda

外围的边 = sisi luar；接缝 = garis di dalam 动画中 6 个三角形一个接一个围着中心摆好，刚好绕满一圈，没有空隙。拼好的图形外面一圈有 6 条边，每条都是原来三角形的一条边，所以一样长。里面那 6 条线是三角形之间的接缝，不算图形的边。 例子：一块六边形饼干切成 6 片三角形，拼回去还是六边形。 注意：只数外面那一圈，里面的线不算。

outer sides = sisi luar; joins inside = garis di dalam In the animation the 6 triangles are placed one after another round the centre and fill a full turn with no gaps. The finished shape has 6 sides round the outside, each one a side of one of the small triangles, so they are all equal. The 6 lines inside are joins between triangles, not sides of the new shape. Example: a hexagon biscuit cut into 6 triangle pieces makes a hexagon again when put back. Watch out: count only the ring of sides outside, not the lines inside.

数新图形的边 = kira sisi bentuk baharu 新图形只看外面一圈：6 条边。如果把里面的接缝也算进去，会数成 12 条；如果把 6 个三角形各 3 条边全部加起来，会数成 18 条。这两个都是常见错误。新图形的边只有外围的 6 条。 例子：4 块正方形拼成一个大正方形，大正方形还是只有 4 条外边。 注意：拼起来以后，贴在一起的边就藏在里面了。

counting sides of the new shape = kira sisi bentuk baharu Look only at the outside ring of the new shape: 6 sides. Counting the joins inside as well gives 12, and adding up all 3 sides of each of the 6 triangles gives 18; both are common mistakes. The new shape has just the 6 outer sides. Example: 4 squares joined into a big square still give a big square with only 4 outer sides. Watch out: once pieces are joined, the sides pressed together are hidden inside.

四个三角形 = empat segi tiga 四个一样的等边三角形：三个尖朝上，中间一个倒过来，拼成一个更大的三角形。外面一圈只有 3 个角，所以还是三角形，每条大边由两条小边连成。不是六边形，也不是正方形。 例子：三角形的饭团盒也常用这样的方法分成 4 格。 注意：外边上连成一直线的两条小边，只算一条大边。

four triangles = empat segi tiga Four equal equilateral triangles, three pointing up and one upside down in the middle, make a bigger triangle. The outside has only 3 corners, so it is still a triangle, and each big side is made of two small sides in a straight line. It is not a hexagon or a square. Example: a triangle lunch box is often split into 4 sections this way. Watch out: two small sides lying in one straight line count as one big side.

描底面 = surih tapak 把三角棱柱立在纸上，让一个三角形的底面贴着纸。用笔沿着底面的边描一圈，再把棱柱拿开。纸上留下的就是一个三角形，跟棱柱的底面一模一样。所以描出来的形状，告诉我们棱柱的底面是什么形状。 例子：把茶叶罐放在纸上描一圈，会得到一个圆形。 注意：描的时候要压住棱柱，不要让它移动。

tracing the base = surih tapak Stand the triangular prism on paper with a triangle base flat on the sheet. Run a pencil round the edges of the base, then lift the prism away. What is left on the paper is a triangle, exactly the same as the prism's base. So the traced shape tells us the shape of the prism's base. Example: tracing round a tea tin placed on paper gives a circle. Watch out: hold the prism still while tracing so that it does not slide.

配对活动和结果 = padankan aktiviti dan hasil 6 个三角形围着中心拼 → 外面 6 条边 → 正六边形。4 个三角形拼 → 外面 3 个角 → 大三角形。描三角棱柱的底面 → 三角形。描正方体的底面 → 正方形。拼合看外围，描画看底面。 例子：描长方体最长的那一面，会得到长方形。 注意：拼合题只数外边；描画题看贴着纸的那个面。

matching activities and results = padankan aktiviti dan hasil 6 triangles round a centre give 6 outer sides, a regular hexagon. 4 triangles give 3 outer corners, a bigger triangle. Tracing the base of a triangular prism gives a triangle, and tracing a cube gives a square. For joining, look at the outline; for tracing, look at the base. Example: tracing the long face of a cuboid gives a rectangle. Watch out: in joining questions count only the outer sides; in tracing questions look at the face touching the paper.