如图所示,直线a、b被直线c所截.
(1)若∠1=∠3,则_____∥____,根据是___________;
(2)若∠2=70°,∠4=70°,则_____∥____,根据是___________;
(3)若∠2=68°,∠3=112°,则_____∥____,根据是___________.
如图所示,直线a、b被直线c所截.
(1)若∠1=∠3,则_____∥____,根据是___________;
(2)若∠2=70°,∠4=70°,则_____∥____,根据是___________;
(3)若∠2=68°,∠3=112°,则_____∥____,根据是___________.