Need ! what is the area of the shaded region?

The figure shows two triangles. To find the the area of the shaded region, you have to substract the area of the larger triangle by the area of the smaller:

 1. Area of the larger triangle:

 A1=bxh/2

 b=5 mm

 h=2mm+4mm+6mm=12 mm

 Then:

 A1=5 mmx12mm/2
 A1=30 mm²

 2. The area of the smaller triangle, is

 A2=bxh/2

 b=3 mm
 h=4 mm

 Then, you have:

 A2=3 mmx4 mm/2
 A2=6 mm²

 3. The area of the shaded region is:

 A3=A1-A2
 A3=30 mm²-6mm²
 A3=24 mm²

 4. Therefore, the answer is: 24 mm²

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