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不规则图形的周长 = perimeter bentuk L 这个图形像字母 L，有六条外边。从左上角开始，顺着外边走一圈，把每一段的格数记下来，最后加起来。拐进去的那两段也要算，因为它们也是外边。 例子：一个两格长、两格宽的正方形，周长 2 + 2 + 2 + 2 = 8 个单位。 注意：数格子里有几格，得到的是另一种量，不是周长。

perimeter of an L-shape = perimeter bentuk L This shape looks like the letter L and has six outside edges. Start at the top-left corner, walk round the outside, note how many units each part is, then add them. The two edges that turn inwards also count, because they are outside edges too. Example: a square two units long and two units wide has perimeter 2 + 2 + 2 + 2 = 8 units. Watch out: counting the squares inside measures something else, not the perimeter.

正五边形徽章 = lencana pentagon sekata 正五边形有五条一样长的边。周长是边数乘一条边的长度。先确认五边形有几条边，再乘。 例子：一个正八边形每边 2 cm，周长 8 × 2 = 16 cm。 注意：答案要写上长度单位。

regular pentagon badge = lencana pentagon sekata A regular pentagon has five equal sides. Its perimeter is the number of sides times the length of one side. First be sure how many sides a pentagon has, then multiply. Example: a regular octagon with 2 cm sides has perimeter 8 × 2 = 16 cm. Watch out: write the length unit with your answer.

三条边相加 = tambah tiga sisi 直角三角形的三条边长度都不同，周长就是把三条边加起来。可以列竖式，个位对齐，满十进一。 例子：边长 7 cm、24 cm、25 cm 的三角形，周长 7 + 24 + 25 = 56 cm。 注意：列竖式时，个位要对齐。

adding three sides = tambah tiga sisi The three sides of this right-angled triangle are all different, so the perimeter is their sum. Use the column method if you like: line up the ones and carry when you reach ten. Example: a triangle with sides 7 cm, 24 cm and 25 cm has perimeter 7 + 24 + 25 = 56 cm. Watch out: line up the ones digits when you add in columns.

正方形的周长 = perimeter segi empat sama 正方形四条边一样长，所以周长是四乘边长。也可以四条边一一相加，得到一样的结果。 例子：边长 15 m 的正方形草地，周长 4 × 15 = 60 m。 注意：算完后，把四条边一一相加来核对。

perimeter of a square = perimeter segi empat sama A square has four equal sides, so its perimeter is four times the side. Adding the four sides one by one gives the same result. Example: a square lawn with 15 m sides has perimeter 4 × 15 = 60 m. Watch out: when you finish, check by adding the four sides one by one.

等边三角形的周长 = perimeter segi tiga sama sisi 等边三角形三条边都一样长，周长就是三乘边长。乘法算不熟时，可以写成三个相同的数相加。 例子：边长 12 cm 的等边三角形，周长 3 × 12 = 36 cm。 注意：算完用加法核对一次。

perimeter of an equilateral triangle = perimeter segi tiga sama sisi All three sides of an equilateral triangle are equal, so the perimeter is three times the side. If multiplying is hard, add the same number three times. Example: an equilateral triangle with 12 cm sides has perimeter 3 × 12 = 36 cm. Watch out: check your answer once by adding.