Total Area = 26 x 10 = 260

Each rectangle’s area = 260 / 13 = 20

x = 20/10 = 2cm  (Area/side 10cm)

y = 20/8 = 2.5 cm  (8 because there are 8 rectangles of that size and the side given up there is 20)

z = 20/20 = 1 cm  (Area / side 20cm)