Respuesta :

Answer:

Yes, this is true.

Step-by-step explanation:

If you substitue x for -1 you get -3(-1+8)=-21, Then you add -1 and 8 so you should get 7. After, you multiply 7 times -3 you get -21. Proving this statement is correct.

Answer:

See below.

Step-by-step explanation:

We can solve for x:

−3(x+8) = −21

Distribute the -3 over the parentheses:

-3x - 24 = -21

Add 24 to both sides:

-3x -24 + 24 = -21 + 24

-3x = 3

Divide both sides by -3:

x = -1.

So that proves the original equation.