Solv for x for all of these 1. 3x+6=21 2. 33=7x-9 3. 28=7+x need to know now please help

Step-by-step explanation:

1.

Move constant to right hand side and change its sign

⇒

Subtract 6 from 21

⇒

Divide both sides of the equation by 3

⇒

Calculate

⇒

--------------------------------------------------------

2.

Swap the sides of the equation

⇒

Move constant to right hand side and change it's sign

⇒

Add the numbers

⇒

Divide both sides of the equation by 7

⇒

Calculate

⇒

---------------------------------------------------------

3.

Swap the sides of the equation

⇒

Move constant to right hand side and change it's sign

⇒

Subtract 7 from 28

⇒

Hope I helped!

Best regards!!

b.-4 units

all you   do is count how many times you move