Simple question
slope of on le diagonal,whose coordinates are given=
[tex] \frac{y2 - y1}{x2 - x1} = \frac{5 - 3}{ - 6 - 2} = \frac{2}{ - 8} or \: \frac{ - 1}{4} [/tex]
now we know that diagonals of square are perpendicular to each other
and we also know that if there are two perpendicular lines have slope m1 and m2 respectively,then
[tex]m1 = \frac{ - 1}{m2} [/tex]
so if one diagonal's slope is -1/4 then other diagonal's slope will be 4
now we know that all the equation of a line is in the form
y=mx+c
where m is slope
so simply put the value of m=4
y=4x+c...i)
we also know that the line of equationi) will pass through the midpoint coordinates of first diagonal
mid point of first diagonal ={(2-6)/2 ,(5+3)/2}=(-2,4)
put this value of x and y in i) equation
4=-8+c
c=12
hence putting the value of c in equation I) we get the equation of line as
y=4x+12
y-4x-12=0