How do you solve #20- 5x = 12- 9x#?

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Answer 1 · 2017-07-16T13:16:16

See a solution process below:

First, subtract #color(red)(20)# and add #color(blue)(9x)# to each side of the equation to isolate the #x# term while keeping the equation balanced:

#-color(red)(20) + 20 - 5x + color(blue)(9x) = -color(red)(20) + 12 - 9x + color(blue)(9x)#

#0 + (-5 + color(blue)(9))x = -8 - 0#

#4x = -8#

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

#(4x)/color(red)(4) = -8/color(red)(4)#

#(color(red)(cancel(color(black)(4)))x)/cancel(color(red)(4)) = -2#

#x = -2#