The question is about elasticity e x,y and this important different of e y,x the ! doesn't mean thing it just to notify it is x,y not y,x

I tried to solve it to make it easier to understand the question the question use calculas

PLEASE check my answer whither it is right or not and correct me

4. Determine the elasticity ex,y (!) when y = a. x.ex,y Y = a . x 2 = dx . X X 1- find X ~ X : 2. find dx b a 7 = dx X a X = a = a = b