Giải thích các bước giải:

 c.Ta có:

$\hat F=90^o-\hat E=58^o$

$\sin E=\dfrac{DF}{EF}\to EF=\dfrac{DF}{\sin E}=\dfrac9{\sin32^o}$

$\cos E=\dfrac{DE}{EF}\to EF=\dfrac{DF}{\cos E}=\dfrac9{\cos32^o}$

d.Ta có:

$QP=\sqrt{HQ^2-HP^2}=\sqrt{13^2-9^2}=2\sqrt{22}$

$\sin Q=\dfrac{HP}{HQ}=\dfrac9{13}\to \hat Q=\arcsin\dfrac9{13}\approx 44^o$

$\hat H=90^o-\hat Q=46^o$