How do you solve #7u - 8= 3u#?

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Answer 1 · 2017-07-15T17:50:58

See a solution process below:

First, add #color(red)(8)# to each side of the equation:

#7u - 8 + color(red)(8) = 3u + color(red)(8)#

#7u - 0 = 3u + 8#

#7u = 3u + 8#

Next, subtract #color(red)(3u)# from each side of the equation to isolate the #u# term while keeping the equation balanced:

#7u - color(red)(3u) = 3u - color(red)(3u) + 8#

#(7 - color(red)(3))u = 0 + 8#

#4u = 8#

Now, divide each side of the equation by #color(red)(4)# to solve for #u# while keeping the equation balanced:

#(4u)/color(red)(4) = 8/color(red)(4)#

#(color(red)(cancel(color(black)(4)))u)/cancel(color(red)(4)) = 2#

#u = 2#