Question

If x²y²=4(xy-1),then prove that xy vary inversely as each other

Answer 1

Step-by-step explanation:

${x}^{2} {y}^{2} = 4(xy - 1) \\ {x}^{2} {y}^{2} = 4xy - 4 \\ {x}^{2} {y}^{2} - 4xy + 4 = 0 \\ {(xy - 2)}^{2} = 0 \\ xy - 2 = 0 \\ xy = 2 \\ x = \frac{2}{y}$

X varies inversely as y