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数正多边形的角 = kira sudut poligon sekata 每个顶点都有一个角，所以只要数顶点。顶点很多的时候，先在一个顶点上用手指按住，然后顺时针一个一个数，回到起点就停。 例子：一个正十边形有十个顶点，所以有十个角。 注意：数完以后，换一个起点再数一次核对。

counting the angles = kira sudut poligon sekata Each vertex has one angle, so just count the vertices. When there are many, keep a finger on one vertex and count clockwise one by one, stopping when you get back to the start. Example: a regular decagon has ten vertices, so it has ten angles. Watch out: after counting, count again from a different starting vertex to check.

正方形的角 = sudut segi empat sama 判断角的种类，要拿直角来比较。把一张纸对折两次，折出一个直角，然后把它放在正方形的一个角上，一条边对齐，看另一条边落在直角里面、刚好重合，还是跑到外面。正方形四个角一样大，量一个就够了。 例子：测量书桌的桌角时，把直角纸的一条边贴着桌边，再看另一条边的位置。 注意：比较时纸要放平，顶点要对准。

angles of a square = sudut segi empat sama To name an angle, compare it with a right angle. Fold a sheet of paper twice to make a right angle, place it on one corner of the square with one edge lined up, and see whether the other edge falls inside, exactly on, or outside. A square's four angles are equal, so measuring one is enough. Example: to test the corner of a desk, lay one edge of the folded paper along the desk edge and look where the other edge lies. Watch out: keep the paper flat and put its corner exactly on the vertex.

锐角的正多边形 = poligon sekata bersudut tirus 回想教学屏学过的规律：正多边形的边数会影响每个角的大小。先写出每个名称的边数，再按规律判断它的角和直角比较的结果，找出角比直角小的那一种。 例子：正八边形有八条边，它的角比直角大。 注意：先写边数再判断，不要凭图形大小来猜。

regular polygon with acute angles = poligon sekata bersudut tirus Recall the rule from the teaching screens: the number of sides of a regular polygon affects the size of each angle. Write down the number of sides for each name, use the rule to compare its angle with a right angle, and find the one whose angles are smaller than a right angle. Example: a regular octagon has eight sides and its angles are bigger than a right angle. Watch out: write the number of sides first; do not guess from how big the shape looks.

钝角的数目 = bilangan sudut cakah 这一题分两步。第一步：边数、顶点数和角数有什么关系？先求出这个正多边形有几个角。第二步：回想教学屏，判断这么多条边的正多边形，每个角属于哪一种。两步合起来就能回答。 例子：正方形有四个角，四个都是直角，所以正方形的钝角是零个。 注意：先看清题目问的是哪一种角。

number of obtuse angles = bilangan sudut cakah This question has two steps. Step one: how are the numbers of sides, vertices and angles related? Find how many angles this regular polygon has. Step two: recall the teaching screens and decide which kind each angle of a regular polygon with that many sides is. Put the two steps together to answer. Example: a square has four angles, all right angles, so a square has zero obtuse angles. Watch out: read carefully which kind of angle the question asks about.