How do you solve: #4a - 4 = 8 + a#?

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Answer 1 · 2017-05-25T00:22:24

See a solution process below:

First, add #color(red)(4)# and subtract #color(blue)(a)# to each side of the equation to isolate the #a# term while keeping the equation balanced:

#4a - 4 + color(red)(4) - color(blue)(a) = 8 + a + color(red)(4) - color(blue)(a)#

#4a - color(blue)(a) - 4 + color(red)(4) = 8 + color(red)(4) + a - color(blue)(a)#

#4a - color(blue)(1a) - 0 = 12 + 0#

#(4 - color(blue)(1))a = 12#

#3a = 12#

Now, divide each side of the equation by #color(red)(3)# to solve for #a# while keeping the equation balanced:

#(3a)/color(red)(3) = 12/color(red)(3)#

#(color(red)(cancel(color(black)(3)))a)/cancel(color(red)(3)) = 4#

#a = 4#