Which of the following is a solution for the equation 7x + 21 = 105? 105
15
84
12

x= 12

Step-by-step explanation:

Simplifying

7x + 21 = 105

Reorder the terms:

21 + 7x = 105

Solving

21 + 7x = 105

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '-21' to each side of the equation.

21 + -21 + 7x = 105 + -21

Combine like terms: 21 + -21 = 0

0 + 7x = 105 + -21

7x = 105 + -21

Combine like terms: 105 + -21 = 84

7x = 84

Divide each side by '7'.

x = 12

Simplifying

x = 12

question 1 is 8, question 2 is 9, question 3 is 24

step-by-step explanation:

now, the numbers they give you at the top are the key. from there, you just have to plug and chug! let's try 1, 2, and 3!

key: a=3, b=5, c=6

1. a+5

remember, a=3, so we plug that in to get 3+5=8

2. 15-c

c=6, so we plug that in to get 15-6=9

3. 4b

b=6, so we plug it in to get 4*6=24

time to try the rest on your own! if you put the answers below in a comment, i'll check them for you!

dont know

step-by-step explanation: