For this case we must find the value of the variable "x" of the following equation:
[tex]3 (4x + 6) = 21[/tex]
We apply distributive property to the terms within parentheses:
[tex]12x + 18 = 21[/tex]
We subtract 18 from both sides of the equation:
[tex]12x + 18-18 = 21-18[/tex]
We divide between 12 on both sides of the equation:
[tex]12x = 3[/tex]
[tex]x = \frac {3} {12}\\x = \frac {1} {4}[/tex]
Answer:
[tex]x = \frac {1} {4}[/tex]
