Respuesta :

Answer:

12.0 cm

Step-by-step explanation:

✔️First, find the height, BC, of the trapezium using Pythagorean Theorem.

BC² = 10² - (9 -3)²

BC² = 10² - 6²

BC² = 64

BC = √64

BC = 8 cm

✔️Find AC using Pythagorean Theorem:

AC² = AB² + BC²

AC² = 9² + 8²

AC² = 145

AC = √145

AC = 12.0415946 ≈ 12.0 (3 significant figures)