hutiehua123
春芽
共回答了16个问题采纳率:68.8% 举报
1.B-A=a
B=A+a
=(-1,5)+(1,3)
=(-1+1,5+3)
=(0,8)
2.AB=B-A
=(-1,5)-(1,1)
=(-1-1,5-1)
=(-2,4)
AE=-1/2AB
=-1/2(-2,4)
=(1,-2)
E-A=AE
E=AE+A
=(1,-2)+(1,1)
=(1+1,-2+1)
=(2,-1)
3.AB=B-A
=(2,1)-(-2,-3)
=(4,4)
CD=D-C
=(-7,-4)-(1,4)
=(-8,-8)
AB=-1/2CD
AB与CD共线
1年前
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