Giải thích các bước giải:
a.Ta có :
$MH=ME, NH=NP,\widehat{MHP}=\widehat{NHE}\rightarrow\Delta MHP=\Delta EHN(c.g.c)$
$\rightarrow MP=NE, \widehat{HMP}=\widehat{HEN}\rightarrow MP//NE$
b. Vì $MA=EB,HM=HE,\widehat{HMA}=\widehat{HEB}\rightarrow\Delta MHA=\Delta EHB(c.g.c)$
$\rightarrow\widehat{MHA}=\widehat{EHB}\rightarrow A,H,B$ thẳng hàng
c.Ta có :
$\widehat{KNE}+\widehat{HEN}+\widehat{NHE}=180^o$
$\rightarrow \widehat{NHE}=105^o$
$\rightarrow \widehat{NKE}+\widehat{KEH}=\widehat{NHE}$
$\rightarrow\widehat{KEH}=15^o$