X and Y in the equation are both unknowns.

等式中的X和Y都是未知数。

《牛津词典》

The length of the war is one of the biggest unknowns.

战争的持续时间是其中一个最大的未知数。

《柯林斯英汉双解大词典》

There are so many unknowns in the proposal.

这项提案中的未知数太多了。

《牛津词典》

On Veterans Day,the president traditionally lays a wreath of flowers next to the Tomb of the Unknowns at Arlington National Cemetery near Washington.

VOA: special.2009.11.14

I'm trying to write these two unknowns in terms of these two knowns and you can solve for them.

我会试着将这两个未知量,用这两个已知量表示出来 这样你们就可以求了

耶鲁公开课 - 基础物理课程节选

I want to show you how easy it is to change the code. But, notice, once I've added this I actually have a problem. This is now an under-constrained problem. I have more unknowns than I have equations.

我加上这个条件后,我马上面临一个问题了,这就是现在是一个非约束性问题了,我的未知数比方程数多,你从代数中可以知道。

麻省理工公开课 - 计算机科学及编程导论课程节选

But it's a reminder that the 'known unknowns' in the Spanish case are mainly local.

BBC: Eurozone crisis: what have we learned?

It seems to be that there are so many unknowns with this Middle East Peace Conference.

NPR: Low Expectations for a Mideast Peace Conference

"There are so many unknowns commercially, " said Scott Foraker, who heads Amgen's year-old biosimilars unit.

WSJ: FDA Sets Path for Biotech Drug Copies