the equation of aline passing through x+2y=2 and cutting an intercept equal in magnitude but opposite insign from the axes is given by?

by using intercept form of line x/a +y/b = 1
where a, b are x and y intercepts respectively.
as, intercepts are equal in magnitude and opp. in sign
so, a = -b
​so the equation becomes
x/a +y/(-a) =1
x - y = a ......(1)
comparing equation (1) with x + 2y = 2
1/1 = -1/2 = a/2
a= -1
so equation is x - y = -1

Or 

Simply by another method
as intercepts are equal and opposite in sign
let x intercept =a and y intercept will be = -a
so slope of line = m = a/ -a = -1
by using slope form of line y = mx + c
y = -x +c      (m=-1)
solving above equation with x+2y = 2 gives c