Question

gjw

想請問3、4、5該怎麼做呢

= (3+Zt₁-9-4t)
- 27-12+ = 15 fot
2t==12
+ = -6
4.等腰梯形 ABCD中,AB||CD且AB + CD,且AB=(-3,4),AD=(7,-1),
若M、N分別為 AB、BC 中點,則下列敘述何者正確?
(1) AB + AD=5√2
(2) AC=(4,3)
(3)DC = 2 AB
6
(4)—-—-CD)
+ CB= CÀ
(5)DB - DM - DN.
3
7
7
答(4)(5)
FC = TAB
DM = = = = ²2 DB²+ = /² DÀ - 0
N
DN = = = = DC + = { DB² - Ⓒ
@
@ -0 = M N = 1²/1² BC + = AB
² MN = AC => |AB| = |BC|
N''
M
M A
(1) |(4,3)) (2) AB+B C & AB +AD
= 5
【102 模】
6

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