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