How do you solve #2+6x=7+7x#?

2 Answers
Apr 21, 2018

#x=-5#

Explanation:

#"collect terms in x on one side of the equation and"#
#"numeric values on the other side"#

#"subtract 7x from both sides"#

#2+6x-7x=7cancel(+7x)cancel(-7x)#

#" subtracting 2 from both sides to get the numeric values"#
#"on one side"#

#rArrcancel2-cancel(2)-x=(7-2)#

#rArr-x=5#

#"multiply both sides by "-1#

#-1xx-x=-1xx5#

#rArrx=-5#

#color(blue)"As a check"#

Substitute this value into the equation and if both sides are equal then it is the solution.

#"left "=2+(6xx-5)=2-30=-28#

#"right "=7+(7xx-5)=7-35=-28#

#rArrx=-5" is the solution"#

Apr 21, 2018

#x=-5#

Explanation:

Firstly, remember whatever we do to one side, we must do to the other.

Isolate #x# to one side by subtracting #6x#:

#2+cancel(6x)=7+x#

Isolate #x# again by cancelling out the constant #(7)# by subtracting #7#:

#-5=cancel7+x -> -5=x#