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数方格求面积 = kira petak 先数完整的格子，再看半格：两个半格合起来等于一个完整的格子。把完整格子的个数加上半格拼成的格子数，就是面积，单位是平方单位。 例子：一个图形有 3 个完整格子和 4 个半格，面积 = 3 + 2 = 5 unit persegi。 注意：半格不能当成一整格来数。

counting squares = kira petak Count the whole squares first, then the half squares: two halves make one whole square. Add the whole squares to the squares made from halves to get the area in square units. Example: a shape with 3 whole squares and 4 half squares has an area of 3 + 2 = 5 unit persegi. Watch out: a half square must not be counted as a whole one.

墙上壁画的面积 = luas mural 壁画是长方形，面积 = 长 × 宽。长和宽都用米来量，所以面积的单位是平方米 m²。 例子：一块招牌长 5 m、宽 2 m，面积 = 10 m²。 注意：别把长和宽加起来，也别算成绕一圈的长度。

area of a mural = luas mural The mural is a rectangle, so its area is length × width. Both are in metres, so the area is in square metres, m². Example: a signboard 5 m long and 2 m wide has an area of 10 m². Watch out: do not add the length and width, and do not find the distance around the edge.

正方形面积 = luas segi empat sama 正方形的四条边一样长，长和宽都是边长，所以面积 = 边长 × 边长，单位用平方厘米。 例子：边长 5 cm 的方形手帕，面积 = 5 × 5 = 25 cm²。 注意：边长乘二或者乘四都不是面积。

area of a square = luas segi empat sama All four sides of a square are equal, so the length and the width are both the side. Area = side × side, in square centimetres. Example: a square handkerchief with 5 cm sides has an area of 5 × 5 = 25 cm². Watch out: the side times 2 or times 4 is not the area.

直角三角形面积 = luas segi tiga bersudut tegak 直角三角形里，夹着直角的两条边，一条是底，另一条就是高。用二分之一乘底乘高来算，单位是平方厘米。 例子：两条直角边 8 cm 和 3 cm，面积 = ½ × 8 × 3 = 12 cm²。 注意：底乘高以后一定要取一半。

area of a right-angled triangle = luas segi tiga bersudut tegak In a right-angled triangle, the two sides that form the right angle are the base and the height. Use ½ × base × height, in square centimetres. Example: sides of 8 cm and 3 cm around the right angle give ½ × 8 × 3 = 12 cm². Watch out: always take half after multiplying the base by the height.

已知三角形面积求高 = cari tinggi 三角形面积是底乘高的一半，所以底乘高 = 面积的两倍。先把面积乘二，再除以底，就得到高，单位是厘米。 例子：面积 24 cm²、底 6 cm → 24 × 2 = 48，48 ÷ 6 = 8 cm。 注意：面积减底或加底都没有道理，单位也要写长度单位。

finding the height = cari tinggi A triangle's area is half of base × height, so base × height is double the area. Double the area, then divide by the base to get the height in centimetres. Example: area 24 cm² and base 6 cm → 24 × 2 = 48, and 48 ÷ 6 = 8 cm. Watch out: subtracting or adding the base and the area makes no sense, and the height needs a unit of length.