Question

19. Solve the equation 3(x - 7) = 42.
• A. 21
B. 49
C. 36
D.7

Answer 1

For this case we must solve the following equation:

$3 (x-7) = 42$

Applying distributive property to the terms within the parenthesis we have:

$3x-21 = 42$

Adding 21 to both sides of the equation:

$3x = 42 + 21\\3x = 63$

Dividing between 3 on both sides of the equation:

$x = \frac {63} {3}\\x = 21$

Answer:

$x = 21$

Answer 2

Answer:

The correct answer is option A.  21

Step-by-step explanation:

It is given an expression in variable x, 3(x - 7) = 42

To find the value of x

Let  3(x - 7) = 42

3x - (3 * 7) = 42   (Open the bracket)

3x - 21 = 42

3x = 42 + 21

3x = 63

x = 63/3 = 21

Therefore the value of x = 21

The correct answer is option A.  21