multiply both sides by 144 (which is 9 x 16)
(144)(-x/9)=(144)(1/16)
16(-x) = 9(1)
-16x = 9
x = /9/16
you could just 'cross-multiply' to get the same result faster:
(-x)(16) = 1(9)
x = -9/16
In general find the lowest common denominator of your fractions, and multiply each term by that.
This will guarantee that all your denominators will cancel, and your fractions will disappear.