the questions is
1. -2+3-9+7+2-8=-___+___
.i do not know can you help me?
a+b=23
b+c=19
c+a=8
a=___ b=___ c=___
it is a homework help me
maths
2007-06-28 7:48 pm
回答 (7)
2007-06-28 7:59 pm
✔ 最佳答案
1.-19+12
a+b+c
=(23+19+8)/2
=25
25-a-b
=25-23(a+b=23)
=2
c=2
25-b-c
=25-19(b+c=19)
6
a=6
25-c-a
=25-8(c+a=8)
=17
b=17
a=6 b=17 c=2
參考: ~myself~
2007-06-29 4:47 am
1. -2 + 3 - 9 + 7 + 2 - 8= -19 + 12
a+b=23 --------(1)
b+c=19 ---- b = 19 - c
c+a=8 ------ a = 8 - c
sub a,b into (1)
8 - c + 19 - c = 23
27 - 2c = 23
27 - 23 = 2c
4 = 2c
c = 2
sub c into last 2 formulas
b + 2 = 19
b = 17
2 + a = 8
a = 6
a=6 b=17 c=2
a+b=23 --------(1)
b+c=19 ---- b = 19 - c
c+a=8 ------ a = 8 - c
sub a,b into (1)
8 - c + 19 - c = 23
27 - 2c = 23
27 - 23 = 2c
4 = 2c
c = 2
sub c into last 2 formulas
b + 2 = 19
b = 17
2 + a = 8
a = 6
a=6 b=17 c=2
2007-06-28 8:31 pm
a+b=23 -----(1)
b+c=19 -----(2)
c+a=8 -------(3)
from (1),
a+b=23
then, a=23-b -----(4)
from (2)
b+c=19
then, c=19-b ----(5)
put (4) & (5) into (3)
--> (23-b) +(19-b) =8
b=17
a=23-b ---> a=6
c=19-b ---> c=2
b+c=19 -----(2)
c+a=8 -------(3)
from (1),
a+b=23
then, a=23-b -----(4)
from (2)
b+c=19
then, c=19-b ----(5)
put (4) & (5) into (3)
--> (23-b) +(19-b) =8
b=17
a=23-b ---> a=6
c=19-b ---> c=2
參考: me
2007-06-28 8:02 pm
1. -2 + 3 - 9 + 7 + 2 - 8= -19 + 12
a+b=23 --------(1)
b+c=19 ---- b = 19 - c
c+a=8 ------ a = 8 - c
sub a,b into (1)
8 - c + 19 - c = 23
27 - 2c = 23
27 - 23 = 2c
4 = 2c
c = 2
sub c into last 2 formulas
b + 2 = 19
b = 17
2 + a = 8
a = 6
a=6 b=17 c=2
a+b=23 --------(1)
b+c=19 ---- b = 19 - c
c+a=8 ------ a = 8 - c
sub a,b into (1)
8 - c + 19 - c = 23
27 - 2c = 23
27 - 23 = 2c
4 = 2c
c = 2
sub c into last 2 formulas
b + 2 = 19
b = 17
2 + a = 8
a = 6
a=6 b=17 c=2
參考: MEMEME
2007-06-28 7:56 pm
a+b=23
a=23-b....(1)
b+c=19
c=19-b....(2)
SUB(1)and(2)
c+a=8
19-b+23-b=8
2b=34
b=17
so,,(1)--->a=23-b
a=6
(2)--------->c=19-b
c=2
***a=6,b=17,c=2
a=23-b....(1)
b+c=19
c=19-b....(2)
SUB(1)and(2)
c+a=8
19-b+23-b=8
2b=34
b=17
so,,(1)--->a=23-b
a=6
(2)--------->c=19-b
c=2
***a=6,b=17,c=2
參考: me=]
2007-06-28 7:55 pm
1. -19+12
b=23-a
b=19-c
c=8-a
so b=19-8+a
=11+a
and 23-a=11+a
a=6
b=17, c=2
b=23-a
b=19-c
c=8-a
so b=19-8+a
=11+a
and 23-a=11+a
a=6
b=17, c=2
參考: me!!
2007-06-28 7:53 pm
a=6,b=17,c=2
收錄日期: 2021-04-12 20:01:31
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