Hello.
First of all, let the number be t.
8 times t can be written like this:
![\mathrm{8t}](https://img.qammunity.org/2023/formulas/mathematics/college/8cafbenonp6ec9ok8uwvjx9quj70kwo996.png)
Notice that the number is before the variable and the times sign (×) is not there.
We can write it as 8×t, but we usually write it as 8t.
The sum of means we add:
8t+21
Now, "less than" is "<" :
![\mathrm{8t+21 < -16}](https://img.qammunity.org/2023/formulas/mathematics/college/6stczfgh4neqd04ej6s692xh3j7lrk88rv.png)
Therefore, the answer is
![\mathrm{8t+21 < -16}](https://img.qammunity.org/2023/formulas/mathematics/college/6stczfgh4neqd04ej6s692xh3j7lrk88rv.png)
I hope it helps.
Have a nice day.
![\boxed{imperturbability}](https://img.qammunity.org/2023/formulas/mathematics/high-school/4e5twsd8myuuptqybbee35e90dbwcl3efm.png)