Question

please
help
me

I WILL MARK BRILLIANT​

Answer 1

Answer:

16 cm

Step-by-step explanation:

refer attachment

Answer 2

Answer:

$a^{2} +b^{2} =c^{2}$

Step-by-step explanation:

$a^{2} +12cm^{2} =20cm^{2} \\a^{2} +144=400\\a^{2} = 400-144 \\ a^{2} =\sqrt{256} \\a= 16$