wèi​zhī​shù HSK7

unknown number

Senses

未知数/ 未知數 wèi​zhī​shù unknown number

noun · a variable or quantity whose value is not yet determined in a mathematical equation

这个代数方程包含两个未知数。

未知数/ 未知數 wèi​zhī​shù uncertainty

noun · a factor, situation, or outcome that is not yet known or decided

项目能否成功还是个未知数。

References

erhua_variant 未知数儿/未知數兒 未知数/未知數