Question

A = {(a, b) $\in R\times R$ : |a - 5| < 1, |b - 5| < 1}
Let a - 5 = x, b - 5 = y
Set A contains all points inside |x| < 1, |y| < 1
B = {(a, b) $\in R\times R$ : 4(a - 6)² + 9(b - 5)² $\le$ 36}
Set B contains all points inside or on
$\frac{(x-1{)}^2}{9}+\frac{y}{4}=1$
$(\pm 1, \pm 1)$ lies inside the ellipse $\Rightarrow A \subset B$