How do you solve #9x+12 = 4x+7#?

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Answer 1 · 2016-03-02T13:24:57

#x=-1#

#9x+12=4x+7#

Subtract both sides by #4x#

#rarr9x+12-4x=4x+7-4x#

#rarr5x+12=7#

#rarr5x=7-12#

#rarr5x=-5#

#rArrx=-5/5=-1#

Verify

#9(-1)+12=4(-1)+7#

#-9+12=-4+7#

#3=3#

#:.x=-1#