Which expression is the lcd of these fractions 4/x^2y 20/xy

LCD of 4 and 20

(x^2) y xy

Without any mathematical operations involved, ask yourself how many common variables are in the denominators. x^2 is the same as (x) (x)

so we have 4 and 20

(x) (x) (y) (x) (y)

So what we have in common is one (x) and one (y).

The LCD is xy

The answer is x^2y. i just took this quiz and this is 100% the correct answer!