Answer:
9.4m
Step-by-step explanation:
Let the diagram of the rectangular pyramid be as shown in the attached
If a point C' is selected midway between C and B and F' is selected midway between D and C as shown in pyramid 2
FC can then be computed using pythagoras theorem such that
FC^2 = FC'^2 + CC'^2
FC^2 = (14.6/2)^2 + (9.8/2)^2
FC^2 =53.29 + 24.01
FC^2 = 77.3
FC = sqrt(77.3) = 8.8
To determine the height of the attic, we estimate EF, Pythagoras theorem can be used for triangle EFC
such that EC^2 = EF^2 + FC^2
therefore EF^2 = EC^2 - FC^2
EF^2 = 12.9^2 - 8.8^2
EF^2 = 166.41 - 77.44
EF^2 = 88.97
EF = sqrt(88.97)
EF = 9.4
The height of the attic is therefore 9.4m