$\dfrac{x+y}{x-y}-\dfrac{x-y}{x+y}=\dfrac{5}{2},\ x^2+y^2=90$ সমীকরণ জোটে $x^2-y^2$-এর মান কত?

Question

Accepted Answer

$72$

Answer

$90$

Answer

$18$

Answer

$36$

x+yx−y−x−yx+y=52, x2+y2=90\dfrac{x+y}{x-y}-\dfrac{x-y}{x+y}=\dfrac{5}{2},\ x^2+y^2=90x−yx+y​−x+yx−y​=25​, x2+y2=90 সমীকরণ জোটে x2−y2x^2-y^2x2−y2-এর মান কত?