Write the solution set of the equation ${x^2} + x - 2 = 0$ in roster form.

Examine whether the following statements are true or false :

$\{ a,b\}  \not\subset \{ b,c,a\} $

The number of elements in the set $\{x \in R :(|x|-3)|x+4|=6\}$ is equal to

Given the sets $A=\{1,3,5\}, B=\{2,4,6\}$ and $C=\{0,2,4,6,8\},$ which of the following may be considered as universal set $(s)$ for all the three sets $A$, $B$ and $C$

$\{ 1,2,3,4,5,6,7,8\} $

Make correct statements by filling in the symbols $\subset$ or $ \not\subset $ in the blank spaces:

$\{ x:x$ is a triangle in a plane $\}  \ldots \{ x:x$ is a rectangle in the plane $\} $

Write the following as intervals :

$\{ x:x \in R,3\, \le \,x\, \le \,4\} $