The only other thing that the change in length depends on is that coefficient of linear expansion, represented by the Greek letter alpha.

唯一的其他变化取决于 长度是线性膨胀的程度，用 alpha 表示。

And the equation that we use to describe linear expansion, says that the change in length is equal to what's known as the coefficient of linear expansion

以及我们用来描述线性膨胀的方程 就是长度的变化等于线膨胀的程度。