Given equations are:

y = |x + 3|

y₁ = x + 3, if x + 3 ≥ 0

y₁ = x + 3 …… (1), if x ≥ - 3

And y₂ = - (x + 3), if x + 3 < 0

y₂ = - (x + 3) …… (2), if x < - 3

So, equation (1) is straight line that passes thorough ( - 3,0) and (0,3). Equation (2) is a line passing through ( - 3,0). So, the graph of which is as follows:

(As x is between ( - 6, - 3) in first shaded region equation becomes as y₂ and when x is between ( - 3,0) for the second shaded region equation becomes y₁)

(from equation (2))

Now integrating by applying power rule, we get

Now applying the limits we get

Hence the value of represents the area of the shaded region (as shown in the graph) and is equal to 9 square units.