Question

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

105
15
84
12

Answer 1

12

Step-by-step explanatio

Answer 2

x= 12

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