Answer:
There are 3 possible answers because you didn't state which value was base or height.
Going off the assumption that the base is 15 cm and the height is 8 cm, the area is 60 cm. (same answer if base is 8 cm and height is 15 cm)
A = 1/2(b*h)
A = 1/2(15*8)
A = 1/2(120)
A = 60
Going off the assumption that the base is 17 cm and the height is 8 cm, the area is 68 cm. (same answer if base is 8 cm and height is 17 cm)
A = 1/2(b*h)
A = 1/2(17*8)
A = 1/2(136)
A = 68
Going off the assumption that the base is 15 cm and the height is 17 cm, the area is 127.5 cm. (same answer if base is 17 cm and the height is 15 cm)
A = 1/2(b*h)
A = 1/2(15*17)
A = 1/2(255)
A = 127.5