How do you solve #2( 3+ m ) - 1= 3m + 11#?

1 Answer
Apr 6, 2017

#m=-6#

Explanation:

Given:#" "color(magenta)(2)color(blue)((3+m))-1=3m+11#

Multiply everything inside the bracket by the 2 that is outside giving:

#(color(magenta)(2xx) color(blue)(3))color(blue)(+)(color(magenta)(2xx)color(blue)(m))-1" "=" "3m+11#

#" "6" "+" "2m" "-1" "=" "3m+11#

#" "5+2m" "=" "3m+11#

Subtract #color(red)(2m)# from both sides (removes it from the left)

#" "color(green)(5+2mcolor(red)(-2m)" "=" "3mcolor(red)(-2m)+11)#

#" "5+" "0" "=" "m" "+11#

#" "5" "=" "m+11#

Subtract #color(red)(11)# from both sides (removes it from the right)

#" "color(green)(5color(red)(-11)" "=" "m+11color(red)(-11))#

#" "-6" "=" "m+0#

To comply with convention write this so that the unknown variable (#m#) is on the left

#" "m" "=" "-6#