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

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Answer 1 · 2017-07-15T17:50:58

See a solution process below:

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

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

$7 u - 0 = 3 u + 8$ $7u - 0 = 3u + 8$

$7 u = 3 u + 8$ $7u = 3u + 8$

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

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

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

$4 u = 8$ $4u = 8$

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

$\frac{4 u}{4} = \frac{8}{4}$ $(4u)/color(red)(4) = 8/color(red)(4)$

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

$u = 2$

How do you solve 7u - 8= 3u7u−8=3u7u - 8= 3u?