Respuesta :

Answer: 21.6

Step-by-step explanation:

Use the Pythagorean theorem which is a^2+b^2=c^2

In this case we would have to square the value of GI and HI to get the value of GH squared.

12^2+18^2= 468

Therefore the value of GH would be the sq root of 468 which would be

rounded off 21.6 (to nearest tenth)