Two sets A and B are as under $A=\left\{(a,b)\in R\times R:|a-5|<1 and |b-5|<1\right\}$; $B=\left\{(a,b)\in R\times R:4{(a-6)}^2+9{(b-5)}^2\le 36\right\}$. Then

$A=\left\{\right(a,b)\in R\times R:|a-5|<1,|b-5|<1\}$

Let $a-5=x, b-5=y$

Set A contains all points inside $\left|x\right|<1,\left|y\right|<1$

$B=\left\{(a,b)\in R\times R:4{(a-6)}^2+9{(b-5)}^2\le 36\right\}$

Set B contains all points inside or on $\frac{{(x-1)}^2}{9}+\frac{y^2}{4}=1$

$(\pm 1,\pm 1)$ lies inside the ellipse $\Rightarrow A\subset B$