3/4=x-3/5x?

1 Answer
Mar 9, 2018

#x = 15/8#

Explanation:

#3/4=x-3/5x#

Sometimes it helps to rewrite the problem, I see an invisible 1 in there that may make things easier to think about if I write it in...

#3/4=(1*x)-(3/5*x)#

Now I can clearly see that I have two numbers, 1 and #3/5# being multiplied by #x# and subtracted from each other. Since they are both being multiplied by #x# we can factor that #x# out and work with two constants which makes our lives easier, so lets do that :)

#3/4=x*(1-3/5) = x*(5/5-3/5) = x*(2/5)#

so,
#3/4 = x2/5#

Finally I can multiply both sides by the reciprocal of #2/5#, #5/2#, to isolate x and solve the problem!

#3/4*5/2 = x2/5*5/2 = x = 15/8#

So, #x = 15/8# :D