一个三角形的所有角度之和是180度。

The sum of all the angles of a triangle is 180 degrees.

《柯林斯英汉双解大词典》

一个三角形有三条边。

A triangle has three sides.

youdao

当建筑物倒塌时，它形成了一个三角形，救了我们。

When the building fell down, it made a triangle, and it saved us.

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Need to get the base in. Second thing I want to do, I need to get the height, so I'm going to input a value for the height, also as a float, a floating point.

也就是输入底的值，第二件我想要做的，事情就是得到三角形的高,因此我会输入一个值作为三角形的高，同样也是一个浮点数。

麻省理工公开课 - 计算机科学及编程导论课程节选

So if I were to solve this problem, here's the way I would do it. I would say, first thing I want to do, is I want to input a value for the base as a float.

如果我想要解决这个问题，这就是我要解决它的方式了，第一件我要做的事情就是要,输入一个浮点数作为三角形的底。

麻省理工公开课 - 计算机科学及编程导论课程节选