Question

if 2x + 3y = 9 and xy = -1

Answer 1

2X+3Y = 9

2X = 9-3Y

X = 9-3Y/2.....(1)

XY = -1

Put the value of X in,

XY = -1

9-3Y/2 - Y = -1

18-3Y-2Y / 2 = -1

18-5Y = -2

-5Y = -2-16

-5Y = -18

Y = 18/5

X = 9-3Y/2

Put value and solve