Given the expression three less that a number what is the value the expression if the number is equal to -17

-17 - 3 = -20

Step-by-step explanation:

Let's start by representing the equation numerically, with x representing "a number." Less than tells us to subtract:

x - 3

Now the problem says that "the number" is equal to -17, so plug in -17 for x.

-17 - 3 = -20

(If this is difficult, think of it like -17 + -3 = -20. That always helps me!)