直角三角形

For example, if you draw a triangle on a flat piece of paper the sum of its angles is equal to two right angles (as you know from elementary geometry ).

比如说，如果你在一张平坦的纸张上画一个三角形，它所有内角之和等于两个直角之和（如你从初等几何中所知的）。

DABC is a right-angled isosceles triangle with A = 90°.

A23。 DABC 为一直角等腰三角形，而 A = 90°。

He unbuttoned successively in reversed direction waistcoat, trousers, shirt and vest along the medial line of irregular incrispated black hairs extending in triangular convergence from the pelvic basin over the circumference of the abdomen and umbilicular fossicle along the medial line of nodes to the intersection of the sixth pectoral vertebrae, thence produced both ways at right angles and terminating in circles described about two equidistant points, right and left, on the summits of the mammary prominences.

他那双手的轨迹从参差不齐、卷缩起皱的黑色体毛的中心线——也就是自骨盆底到下腹部肚脐眼周围那一簇簇体毛，又沿着节结的中心线进而延伸到第六胸脊椎的交叉点，从这里又向两侧丛生，构成直角形，在左右等距离的两个点，即环绕乳头顶端形成的三角形收敛图形的中心线——穿行。

Given that is a right angle in triangle ,, and , find the value of .

已知三角形中的为一直角，，及

A triangle with one right angle .

有一个直角的三角形。

The three antennas which receive VHF impulses emitted by a lightning discharge are placed on the vertices of a right-angled isosceles triangle with perpendicular sides 120 meters in length.

三个接收天线(接收闪电放电辐射的超高频脉冲)分别放在一个垂直边长为120米的直角等腰三角形的顶点，由到达天线的时间差来计算接收到的闪电脉冲的方向。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。