I already have asked $2$ questions on similar topics. In that questions I have equations of parabola and line. And equations have $y$ and $x$ variable.

But in this question I have functions.

$$f(x) = |x| - 1 \quad\mbox{and}\quad g(x) = 1 - |x|.$$

a) Sketch their graphs.

b) Using integration find the area of the bounded region. 

In other two questions I know how to find values of $x$ and $y$ using substitution. But in this question because of $f(x)$ and $g(x)$. I am clueless how to start.

Please provide answer in detail.

My attempt is only.

$f(x) = x - 1, -x - 1$

$g(x) = 1 - x, 1 + x$.