How do you simplify `(3 sqrt x- sqrt y)( sqrt x-4 sqrt y)`?

Related questions

• How do you simplify `\frac{2}{\sqrt{3}}`?
• How do you multiply and divide radicals?
• How do you rationalize the denominator?
• What is Multiplication and Division of Radicals?
• How do you simplify `7/(""^3sqrt(5)`?
• How do you multiply `(sqrt(a) +sqrt(b))(sqrt(a)-sqrt(b))`?
• How do you rationalize the denominator for `\frac{2x}{\sqrt{5}x}`?
• Do you always have to rationalize the denominator?
• How do you simplify `sqrt(5)sqrt(15)`?
• How do you simplify `(7sqrt(13) + 2sqrt(6))(2sqrt(3)+3sqrt(6))`?