Question

If 4 x² +9 y²=18 and xy=1, find the value of(2x-3y)

Answer 1

(2x-3y)²= (2x)²+(9y)²-2xy
=4x²+9y²-2
=18-2
=16
so, 2x-3y=√16
= 4

Answer 2

Answer:

4 by 3 minus 3 by 4 and whole square + 2 equal 16 by 9 m square + 9 by 16 n square