We need to find the area of the region where all three conditions are satisfied:
∣x∣−y≤1, y≥0, and y≤1
Rewrite the first inequality as y≥∣x∣−1.
Since ∣x∣=x when x≥0 and ∣x∣=−x when x<0:
- When x≥0: y≥x−1
- When x<0: y≥−x−1
Find the key intersection points by solving where boundary lines meet:
Where y=x−1 meets y=0: 0=x−1, so x=1
Point: (1,0)
Where y=−x−1 meets y=0: 0=−x−1, so x=−1
Point: (−1,0)
Where y=x−1 meets y=1: 1=x−1, so x=2
Point: (2,1)
Where y=−x−1 meets y=1: 1=−x−1, so x=−2
Point: (−2,1)
From y≥∣x∣−1, we get ∣x∣≤y+1
This means −(y+1)≤x≤(y+1)
For any y between 0 and 1, the width of the region is 2(y+1)
The region forms a trapezoid:
At y=0: width =2(0+1)=2 (from x=−1 to x=1)
At y=1: width =2(1+1)=4 (from x=−2 to x=2)
Height =1−0=1
Area of trapezoid:
Area=21×(sum of parallel sides)×height
Area=21×(2+4)×1=21×6×1=3
The area of the region is 3 square units.