Question

How do i find the value of variables

Answer 1

$f^2+e^2=13^2\\ 4^2+d^2=f^2\\ 9^2+d^2=e^2\\\\ f^2+e^2=169\\ 16+d^2=f^2\\ 81+d^2=e^2\\\\ 16+d^2+81+d^2=169\\ 2d^2=72\\ d^2=36\\ d=6\\\\ f^2=16+36\\ f=52\\ f=\sqrt{52}=2\sqrt{13}\\\\ e^2=81+36\\ e^2=117\\ e=\sqrt{117}$