Question

X+y=13
x-y=3
prove that
xy-1=x²-y²

Answer 1

Answer:

From eq(i) we get :-

x= 13-y

Putting value of x in eq(ii) we get :-

13- y - y =3

=> 13-2y =3

=> -2y = 3-13

=> -2y = -10

:. y = 5

Putting valuebof y in eq(i) we get :-

x= 13-5

x= 8

Proving part :

xy -1 = x² - y²

8*5 -1 = 8² - 5²

40-1 = 64- 25

39= 39 ( Proved )

Step-by-step explanation:

Hope it helps you