Question

chứng minh z=x+y

Answer 1

\(\Delta ABC\) có : x + y + \(\widehat{ACB}\) = 180^o  ( tổng 3 góc trong 1 \(\Delta\) )

Mà \(\widehat{ACB}+z=180^o\) \(\Rightarrow z=x+y\left(đpcm\right)\)

Answer 2

Có: \(\widehat{ACB}+x+y=180^o\)

Mà: \(z+\widehat{ACB}=180^o\)

\(\Rightarrow x+y=z\)