a: \(\widehat{N}+\widehat{Q}=360^0-60^0-70^0=230^0\)
mà \(\widehat{N}-\widehat{Q}=20^0\)
nên \(\widehat{N}=\dfrac{230^0+20^0}{2}=125^0\)
\(\widehat{Q}=125^0-20^0=105^0\)
b: \(\widehat{Q}+\widehat{N}=360^0-110^0-70^0=180^0\)
\(\Leftrightarrow4\cdot\widehat{N}=180^0\)
=>\(\widehat{N}=45^0\)
\(\widehat{Q}=3\cdot45^0=135^0\)