Question

6．點(diǎn)A（a，3）與點(diǎn)B（-1，b）關(guān)于y軸對(duì)稱，則a+b=4．

Answer 1

分析 關(guān)于y軸對(duì)稱的點(diǎn)，縱坐標(biāo)相同，橫坐標(biāo)互為相反數(shù)，可得答案．

解答 解：A（a，3）與點(diǎn)B（-1，b）關(guān)于y軸對(duì)稱，得
a=1，b=3．
a+b=4，
故答案為：4．

點(diǎn)評(píng) 本題考查了關(guān)于y軸對(duì)稱的點(diǎn)的坐標(biāo)，解決本題的關(guān)鍵是掌握好對(duì)稱點(diǎn)的坐標(biāo)規(guī)律：關(guān)于x軸對(duì)稱的點(diǎn)，橫坐標(biāo)相同，縱坐標(biāo)互為相反數(shù)；關(guān)于y軸對(duì)稱的點(diǎn)，縱坐標(biāo)相同，橫坐標(biāo)互為相反數(shù)；關(guān)于原點(diǎn)對(duì)稱的點(diǎn)，橫坐標(biāo)與縱坐標(biāo)都互為相反數(shù)．