the equation -3x-9=-21 is solved as follows supply the correct numbers to complete the solution

-3x=? add 9 to both sides
x=? divide both sides by -3

1 answer

To solve the equation -3x-9=-21, we can follow these steps:

Step 1: Start with the equation -3x-9=-21.

Step 2: Add 9 to both sides of the equation to isolate the term with x. It becomes:

-3x - 9 + 9 = -21 + 9

Simplifying, we have:

-3x = -12

Step 3: To solve for x, divide both sides of the equation by -3:

(-3x) / -3 = (-12) / -3

Simplifying, we get:

x = 4

Therefore, the value of x that satisfies the equation -3x-9=-21 is x = 4.