Question

12x+13y=29' 13x+12y=21. find x+y​

Answer 1

Answer is in the attachment

Answer 2

$\huge\underline\mathfrak\blue{Answer-}$

$\huge\sf\boxed{x\:=\:-3}$

$\huge\sf\boxed{y\:=\:5}$

$\huge\underline\mathfrak\blue{Explanation-}$

Refer to the attachment.

*Note - In these type of Questions, we have to add the equations and then subtract the equations as multiplying both equations isn't easy to solve and take time. So by adding and subtracting seperately is easy.