How do you solve #2x + 31= - 7( 1- 3x )#?

1 Answer
Oct 6, 2016

#x=2#

Explanation:

You are given: #2x+31=-7(1-3x)#

Use the distributive property to distribute the #-7# to #(1-3x)#. The equation should end up looking like this:

#2x+31=-7(1-3x)#
#2x+31=(-7)(1)-(-7)(3x)#
#2x+31=-7+21x#

Next, you want to get all of the variables #(x)# on one side of the equation, and all of the number part on the other side. First subtract #-7# from both sides; then subtract #2x# from both sides.

#2x+31=-7+21x#
#2x-(2x)+31-(-7)=-7-(-7)+21x-(2x)#
#cancel(2x-(2x))+31-(-7)=cancel(-7-(-7))+21x-(2x)#

After simplifying, you should be left with:
#38=19x#

Divide both sides by #19# to get #x# by itself.
#38/19=(19x)/19#
#2=x#