If `[xx-y2x+y7]=[3 1 8 7]` , then find the value of `ydot`

If [x-y2x+y7]=[3187], then find the value of y.

If [[x,x-y],[2x+y,7]]=[[3,1],[8,7]] then find the value of y.

If |(x, x-y),(2x+y,7)|=|(3, 1),( 8, 7)| , then find the value of y

If x-2y =-1 , 2x-y = 7 then find the value of x-y .

If [(x,x-y),(2x+y,7)]=[(3,1),(8,7)] write the value of y.

(i) x+2y=-7 and 3x-2y=-1, then find the value of x. (ii) If x+y=8 and 4y-x=2, then find the value of y. (iii) If 3x+5y=9 and 5x+3y=7, then find the value of x+y. (iv) If 3x-y=11 and x-3y=17, then find the value of x-y.

If 4x^2+y^2=40 and x y=6, find the value of 2x+ydot

If 2x+3y=34 and (x+y)/(y)=(13)/(8), then find the value of 5y+7x