`x^2 - y^2 = 12` i. `(x - y)(x + y) = 12` বা, `(x - y) .6 = 12` বা, `x - y = 12/6` বা, `x - y = 2` বা, `(x - y)^2 = 4` ii. `x + y = 6` `x - y = 2` `:. (2x = 8)/(x = 4)` iii. `y = 6-4 = 2 :. xy = 4 xx 2 = 8` [ ন. প্র. কু. বো. ]