a) $S_{MNH}$ = $\frac{1}{2}$.MH.NH =$\frac{1}{2}$ .12.6 =$36 cm^{2}$
$S_{ENH}$ = $\frac{1}{2}$ .EN . NH = $\frac{1}{2}$ .6.6 = $18cm^{2}$
⇒ $S_{MEH}$ = $36^{}$ - $18=^{}$ $18cm^{2}$
b) $S_{MNPQ}$ = $12^{}$ . $12^{}$ = $144 cm^{2}$
⇒ $S_{MQPH}$ = $144^{}$ - $36^{}$ = $108cm^{2}$
c) $\frac{S MEH}{S MQPH}$ = $\frac{18}{108}$ = $\frac{1}{6}$
⇒$6^{}$ . $S_{MEH}$ = $S_{MQPH}$
# uyennhi08032006
