How do you solve #3+ 6x = 18+ x#?

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Answer 1 · 2017-06-02T19:38:46

#x = 3#

Subtract #color(red)x# from both sides:

#3+6x-color(red)x=18+x-color(red)x#

#3+5x = 18#

Now, subtract #color(blue)3# from both sides:

#3 + 5x - color(blue)3 = 18 - color(blue)3#

#5x = 15#

Finally, divide both sides by #color(orange)5#:

#(5x)/color(orange)5 = 15/color(orange)5#

#x = 3#

Final Answer

Answer 2 · 2017-06-02T19:40:06

See a solution process below:

First, subtract #color(red)(3)# and #color(blue)(x)# from each side of the equation to isolate the #x# term while keeping the equation balanced:

#-color(red)(3) + 3 + 6x - color(blue)(x) = -color(red)(3) + 18 + x - color(blue)(x)#

#0 + 6x - color(blue)(1x) = 15 + 0#

#(6 - color(blue)(1))x = 15#

#5x = 15#

Now, divide each side of the equation by #color(red)(5)# to solve for #x# while keeping the equation balanced:

#(5x)/color(red)(5) = 15/color(red)(5)#

#(color(red)(cancel(color(black)(5)))x)/cancel(color(red)(5)) = 3#

#x = 3#