A + B = 180 , B + C =220, A + C = 200
Find A , B , C
Thanks !
F.1 Maths
2007-04-11 2:39 am
回答 (9)
2007-04-11 2:48 am
✔ 最佳答案
A + B = 180 , B + C =220, A + C = 200A + B = 180
+B + C = 220
+C + A = 200
---------------------
(A+B+C)+(A+B+C)=180+220+200
2(A+B+C)=600
A+B+C=300
A+B+C=300
- B+C=220
------------------
A =80
A+B=180
-A =18
-------------
B =100
A+C=200
-A =80
-------------
C =120
A=180
B=100
C=120
參考: 自己
2007-04-11 11:13 pm
(A+B)+(B+C)+(A+C)=2A+2B+2C
180+220+200=2(A+B+C)
600/2=A+B+C
A+B+C=300
300-A+B=C
300-180=C
C=120
300-B+C=A
300-220=A
A=80
300-A+C=B
300-200=B
B=100
2007-04-11 15:16:48 補充：
樓上的大部分人都有點倚賴． ．＆ ． ． ． ．
180+220+200=2(A+B+C)
600/2=A+B+C
A+B+C=300
300-A+B=C
300-180=C
C=120
300-B+C=A
300-220=A
A=80
300-A+C=B
300-200=B
B=100
2007-04-11 15:16:48 補充：
樓上的大部分人都有點倚賴． ．＆ ． ． ． ．
參考: me
2007-04-11 3:33 am
A + B = 180.....................(1)
B + C = 220.....................(2)
A + C = 200.....................(3)
(1),
A + B = 180
B = 180 - A
Subst. B = 180 - A into (2)
180 - A + C = 220...................(4)
(4) - (3),
180 - A + C - (A + C) = 220 - 200
180 - A + C - A - C = 20
180 - 2A = 20
180 = 20 + 2A
160 = 2A
A = 80
Subst. A = 80 into (1)
80 + B = 180
B = 100
Subst. A = 80 into (3)
80 + C = 200
C = 120
Therefore,,A=80,B=100,C=120
B + C = 220.....................(2)
A + C = 200.....................(3)
(1),
A + B = 180
B = 180 - A
Subst. B = 180 - A into (2)
180 - A + C = 220...................(4)
(4) - (3),
180 - A + C - (A + C) = 220 - 200
180 - A + C - A - C = 20
180 - 2A = 20
180 = 20 + 2A
160 = 2A
A = 80
Subst. A = 80 into (1)
80 + B = 180
B = 100
Subst. A = 80 into (3)
80 + C = 200
C = 120
Therefore,,A=80,B=100,C=120
參考: 自己
2007-04-11 3:03 am
先找出其中一個化數 : A=180-B
180-B+ C = 200
180-B+C-180=200 - 180
-B+C=20
-B-(-B)+C =20-(-B)
C= 20+B
THEN
B+C=220
B+20+B=220
2B+20=220
B=100
THEN
C=20+B
C=120
IF A+C=200
A+120=200
A=80
A+C=200
180-B+ C = 200
180-B+C-180=200 - 180
-B+C=20
-B-(-B)+C =20-(-B)
C= 20+B
THEN
B+C=220
B+20+B=220
2B+20=220
B=100
THEN
C=20+B
C=120
IF A+C=200
A+120=200
A=80
A+C=200
2007-04-11 2:48 am
A + B = 180 --------------------- 1
B + C = 220 --------------------- 2
A + C = 200 --------------------- 3
1 :
A + B = 180
i.e. B = 180 - A
subs into 2 :
we get 180 - A + C = 220
i.e. C = 220 -180 + A
C = 40 + A
subs into 3 :
we get A + 40 + A = 200
i.e. 2A = 200 - 40
2A = 160
A = 80
subs into 1 :
80 + B = 180
B = 100
subs into 2 :
100 + C = 220
C = 120
B + C = 220 --------------------- 2
A + C = 200 --------------------- 3
1 :
A + B = 180
i.e. B = 180 - A
subs into 2 :
we get 180 - A + C = 220
i.e. C = 220 -180 + A
C = 40 + A
subs into 3 :
we get A + 40 + A = 200
i.e. 2A = 200 - 40
2A = 160
A = 80
subs into 1 :
80 + B = 180
B = 100
subs into 2 :
100 + C = 220
C = 120
2007-04-11 2:47 am
(A + C)-(A + B )=20
∴C-B=20
假設B:100
C:120
A+100(B)=180
∴A:80
B+120(C)=200
∴A:80
∴A:80
B:100
C:120
P.S.我是P.6學生
∴C-B=20
假設B:100
C:120
A+100(B)=180
∴A:80
B+120(C)=200
∴A:80
∴A:80
B:100
C:120
P.S.我是P.6學生
參考: me
2007-04-11 2:46 am
A=80,C=120
因為C-A=40,
所以A+(A+40)=200
2A=160
A=80
C=A+40
所以C=120
因為C-A=40,
所以A+(A+40)=200
2A=160
A=80
C=A+40
所以C=120
2007-04-11 2:43 am
Question:A + B = 180 , B + C =220, A + C = 200
Answer:
A=80
B=100
C=120
2007-04-10 18:46:14 補充：
A B=180(80) (100)=180B C=220(100) (120)=220A C=200(80) (120)=200.
2007-04-10 18:46:25 補充：
A B=180(80) (100)=180B C=220(100) (120)=220A C=200(80) (120)=200.
2007-04-10 18:51:03 補充：
A=80,C=120BecauseA=40,ThereforeA (A 40)=2002A=160A=80C=A 40所以C=120 BecauseA B=180(80) (?)=180180-80=100Therefore B=100
Answer:
A=80
B=100
C=120
2007-04-10 18:46:14 補充：
A B=180(80) (100)=180B C=220(100) (120)=220A C=200(80) (120)=200.
2007-04-10 18:46:25 補充：
A B=180(80) (100)=180B C=220(100) (120)=220A C=200(80) (120)=200.
2007-04-10 18:51:03 補充：
A=80,C=120BecauseA=40,ThereforeA (A 40)=2002A=160A=80C=A 40所以C=120 BecauseA B=180(80) (?)=180180-80=100Therefore B=100
參考: me
收錄日期: 2021-04-12 23:50:13
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