for irregular shapes, simply cut the shapes into recognizable shapes like square, rectangle, triangle. Solve the area of each shape and add it up to get the total area of the irregular shape.
1) rectangle 1 = 5cm * 3cm = 15cm²
rectangle 2 = 2cm * 4cm = 8cm²
15cm² + 8cm² = 23 cm²
2) rectangle 1 = 9cm * (10cm-6cm) = 9cm * 4cm = 36cm²
rectangle 2 = 6cm * 2cm = 12cm²
36cm² + 12cm² = 48cm²
3) square 1 = (2cm)² = 4cm²
square 2 = (4cm)² = 16cm²
shaded area only. subtraction performed.
16cm² - 4cm² = 12cm²
4) square = (10cm)² = 100cm
triangle = (10cm * 10cm)/2 = 100cm² / 2 = 50cm²
100cm² + 50cm² = 150cm²
5) rectangle 1 = 4mm * 3mm = 12mm²
rectangle 2 = 8mm * 10mm = 80mm²
12mm² + 80mm² = 92mm²
