How do you solve #7x + 9= 51+ x#?

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Answer 1 · 2017-07-29T17:21:32

See a solution process below:

Step 1) Subtract #color(red)(9)# and #color(blue)(x)# from each side of the equation to isolate the #x# term while keeping the equation balanced:

#7x + 9 - color(red)(9) - color(blue)(x) = 51 + x - color(red)(9) - color(blue)(x)#

#7x - color(blue)(x) + 9 - color(red)(9) = 51 - color(red)(9) + x - color(blue)(x)#

#7x - color(blue)(1x) + 0 = 42 + 0#

#(7 - color(blue)(1))x = 42#

#6x = 42#

Step 2) Divide each side of the equation by #color(red)(6)# to solve for #x# while keeping the equation balanced:

#(6x)/color(red)(6) = 42/color(red)(6)#

#(color(red)(cancel(color(black)(6)))x)/cancel(color(red)(6)) = 7#

#x = 7#