1 over 3 should be the answer I think
A^2+b^2=(a+b) (a-b)
Let a^2=x^2 then a^2= x^2
Let b^2=63 them b^2= 64
b=8
Answer: (x+8) (x-8)
For direct variation, y = kx
8 = -4k
k = 8/-4 = -2
Therefore, required equation is y = -2x
when x = 7, y = -2(7) = -14
