How do you solve #3/7 = (x-3)/14#?

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Answer 1 · 2016-12-22T19:32:26

#x=9#

#3/7=(x-3)/14#

#(x-3)/14=3/7" "#multiply both sides by 14

#x-3=(3xx14)/7#

#x-3=42/7#

#x-3=6#

#x=9#

Check: substitute # x= 9#

#3/7=(9-3)/14#

#3/7=6/14#

#3/7=3/7#

Answer 2 · 2016-12-23T16:30:47

A different approach

#x=9#

If you make the denominator of #3/7# be 14 then as both sides have a common denominator you only need to consider the numerators.

Multiply any number or fraction by 1 and you do not change its value. However, 1 comes in many forms.

#color(green)(3/7color(red)(xx1)=(x-3)/14#

#color(green)(3/7color(red)(xx2/2)=(x-3)/14#

#6/14=(x-3)/14#

#=>6=x-3#

#x=9#