How do you solve #2/x=7/9#?

2 Answers
Mar 25, 2018

#=> x = 18/7#

Explanation:

We are given:

#=>2/color(blue)x=7/color(red)9#

If we multiply both sides by #color(red)9color(blue)x#, we get:

#=>(2(color(red)9cancelcolor(blue)x))/cancelx = (7(cancelcolor(red)9color(blue)x))/cancel9#

Now we can simplify and continue solving for #x#.

#=>18=7x#

#=> 18/7=x#

With ratios, this is sometimes referred to as cross-multiplication:

#=>a/b = c/d overset("cross-multiply")-> ad = bc#

Mar 25, 2018

#x=18/7#

Explanation:

#2/x=7/9#

we need to leave #x# on one side.

so times both sides by #x#

we get 7

#2=7/9x#

times both sides by #7/9#

we get

#2*9/7=x#

simplify it and we get

#18/7=x#