Question

please answer that question please​

Answer 1

I think 2nd equation is 13x + 12y = 21

12x + 13y = 29 ---(I)

13x + 12y = 21 ------(ii)

(I) + (ii)

25 x + 25 y = 50

25 (x + y) = 50

X + y = 50/25

X + y = 2

.

. . Ans = 2