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

The equation -3x - 9 = -21 can be solved as follows:

-3x = -21 + 9 (add 9 to both sides)
-3x = -12 (simplify)
x = -12 / -3 (divide both sides by -3)

The correct numbers to complete the solution are:

-3x = -12
x = 4

To solve the equation -3x-9=-21, we will follow the steps given:

1. Add 9 to both sides of the equation to isolate the term with 'x' on one side:
-3x - 9 + 9 = -21 + 9
-3x = -12

Therefore, -3x equals -12.

2. To find the value of 'x', we need to divide both sides of the equation by -3:
(-3x)/(-3) = (-12)/(-3)
x = 4

Therefore, the value of 'x' is 4.

So, the completed solution is:

-3x = -12
x = 4

To solve the equation -3x - 9 = -21, we need to isolate the variable x.

1. Start by adding 9 to both sides of the equation to get rid of the -9 on the left-hand side:
-3x - 9 + 9 = -21 + 9
Simplifying, we have:
-3x = -12

2. Now, we need to solve for x. To do this, divide both sides of the equation by -3:
(-3x) / -3 = (-12) / -3
Simplifying further, we get:
x = 4

So, the solution to the equation is x = 4.

To complete the solution, we have:

-3x = -12
x = 4

By following these steps, we have successfully solved the equation -3x - 9 = -21.