Question

How do you do this question?

Answer 1

We get

$AC^2 + BC^2 = 11^2$

$AD^2 + CD^2 = AC^2$

Adding equations,

$AC^2 + BC^2 + AD^2 + CD^2= 11^2 + AC^2$

$BC^2 + AD^2 + CD^2= 11^2$

For the total sum of squares we need to add $AB^2$

$AB^2 + BC^2 +AD^2 + CD^2= 11^2 + 11^2 = 242$