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看记号认三角形 = kenal segi tiga melalui tanda 给三角形命名，要按图上的记号来判断：先看每条边上有没有等长的短线，再看每个角上有没有小方块或弧线记号。把找到的线索写下来，然后对照分类图里四种三角形的特征，看哪一种完全符合。 例子：一个四边形四个角都有小方块，四条边都有同样的短线，它就是正方形。 注意：按记号判断，不要按图形摆放的方向判断。

naming by marks = kenal segi tiga melalui tanda To name a triangle, go by the marks in the picture: first check each side for short equal-length marks, then check each angle for a small square or an arc. Note the clues you find and compare them with the features of the four kinds of triangle in the chart to see which one fits completely. Example: a four-sided shape with a small square at every corner and the same mark on every side is a square. Watch out: judge by the marks, not by which way the shape is turned.

等边三角形的角 = sudut segi tiga sama sisi 回想分类图里等边三角形的特征：它的边和角各有什么特点？再把它的角一个一个拿来和直角比较，判断每个角属于哪一种，最后数出锐角。 例子：正方形的四个角都是直角，所以正方形有四个直角。 注意：判断角的种类时，一定拿直角来比较。

angles of an equilateral triangle = sudut segi tiga sama sisi Recall the features of an equilateral triangle in the chart: what is special about its sides and its angles? Then compare its angles with a right angle one at a time, decide which kind each one is, and count the acute ones. Example: all four angles of a square are right angles, so a square has four right angles. Watch out: always use a right angle as the yardstick when naming an angle.

按边长分类 = kelaskan mengikut panjang sisi 题目给了三条边的长度。把三个数比一比：三个都一样、只有两个一样、还是三个都不同？比较结果决定三角形的名称。 例子：一个四边形的边长是 5 cm、5 cm、5 cm、5 cm，四条边都一样长。 注意：比较时单位要一样。

sorting by side lengths = kelaskan mengikut panjang sisi The question gives the three side lengths. Compare the three numbers: are all three the same, only two the same, or all different? The result decides the triangle's name. Example: a four-sided shape with sides 5 cm, 5 cm, 5 cm and 5 cm has all four sides equal. Watch out: compare lengths in the same unit.

找钝角三角形 = cari segi tiga bersudut cakah 钝角比直角大。逐个看三个三角形，把每一个角都拿来和直角比较：可以想象把直角纸放在角上，看另一条边会不会跑到纸外面。找到比直角大的角，它所在的三角形就符合题目。 例子：一把打开很大的扇子，扇骨之间的角是钝角。 注意：每个三角形的三个角都要看。

finding the obtuse triangle = cari segi tiga bersudut cakah An obtuse angle is bigger than a right angle. Look at the three triangles in turn and compare every angle with a right angle: imagine a right-angle paper on the angle and see whether the other arm goes outside it. The triangle containing an angle bigger than a right angle is the one asked for. Example: a fan opened very wide makes an obtuse angle between its ribs. Watch out: look at all three angles of every triangle.