Let x be the sum of a and b.

设x为a加b之和。

《牛津词典》

Let x be the equal of y.

设 x 等于y。

《新英汉大辞典》

The R&R database will not let you create a reservation request that it knows will be declined because another reservation was already accepted, so you should not see many red X icons either.

R&R 数据库不允许您创建它知道会被拒绝（因为另一个预订已被接受了）的预订请求，所以您应该不会看到很多红色 X 图标。

youdao

Let's create a graph here that on the x axis it's going to be time, so time zero will be when you first take in a food and then one hour later, two hours later will be shown as you go from left to right, and then we'll have blood glucose level up on the y axis.

我们在这建立一个曲线图,X轴代表的是时间,所以零时间点是你第一次进食的时间,然后一小时以后,两小时以后,是从左到右呈现在图表上的,在Y轴上是你的血糖值

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

Let x be the number of people likely to be telling stories about me.

WSJ: Millions Will Say They Slept With Me

Let's Talk About X will be produced by the ESPN Digital Media team and will feature daily content giving a fans point of view from the X games 16 venues.

ENGADGET: ESPN lays out X Games 16 coverage via online, HD & 3D formats, including in-car 3D cams

Let's be clear: the 1, 792 x 768 resolution ultimately amounts to your garden-variety 1, 366 x 768 with some extra horizontal pixels.

ENGADGET: Toshiba Satellite U845W review: an Ultrabook with a screen size all its own