Question

35x+23y=207and 23x+35y=197

Answer 1

adding both equations, we get

58x+58y=404
x+y=404/58
x=404/58-y ----(1)
putting value of x in any one of the two equations
23{(404/58) - y) }+35y=197
23×404/58 - 23y+35y=197
12y=197 - 23×404/58
$y = \frac{197 - 2 3 \times 404 \div 58}{12}$