Refer to the figure. Find a relationship between a, b and c.
Link:http://img398.imageshack.us/img398/66/85571213da5.png
maths
2008-07-03 11:21 pm
回答 (4)
2008-07-03 11:32 pm
✔ 最佳答案
a + x = 180 ................(1) (adjacent angles on a straight line).x + c = b ....................(2) (exterior angle of triangle).
(1) - (2) we get
a - c = 180 - b.
Therefore, a + b -c = 180.
2008-07-03 11:35 pm
c+180-b=a(三角形外角)
a+b-c=180
a+b-c=180
2008-07-03 11:33 pm
(180-a) +(180-b) +c =180
360-a -b+c =180
a +b-c =180
360-a -b+c =180
a +b-c =180
2008-07-03 11:31 pm
Ans: a+b-c = 180
Let x,y be the angles in the triangle.
x+y+c =180 --- 3
a=180-x ---1
b=180-y ---2
Subsititute euqtion 1 & 2 to 3
Then solve the equation, you will find the answer.
Let x,y be the angles in the triangle.
x+y+c =180 --- 3
a=180-x ---1
b=180-y ---2
Subsititute euqtion 1 & 2 to 3
Then solve the equation, you will find the answer.
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