please tlong bantu bsok d kumpulkan

7. a. L = a x t / 2 = 13x17/2 = 110,5 cm²
8.
AD = 10
AB = 20
CB=CA = 26
DC = √26²-10² = √576 =24
a. k = 20+26+26 = 66 cm
b. L =a.t/2 = 20.24/2 = 240 cm²