Question

七年级的数学题。。。

如图，已知∠AOC和∠AOB的和是180°，OM,ON分别是∠AOC,∠AOB的平分线，且∠MON=40°,求∠AOC和∠AOB的度数。

Answer 1

依题意，
∠AOM = 1/2∠AOC
∠AON = 1/2*∠AOB
∠MON = ∠AOM - ∠AON = 1/2(∠AOC - ∠AOB)
∠AOC - ∠AOB = 80°
__________
解和差问题：
∠AOC = (180+80)/2 = 130°
∠AOB = (180-80)/2 = 50°

Answer 2

依题意，
∠AOM = 1/2∠AOC
∠AON = 1/2*∠AOB
∠MON = ∠AOM - ∠AON = 1/2(∠AOC - ∠AOB)
∠AOC - ∠AOB = 80°
∠AOC = (180+80)/2 = 130°
∠AOB = (180-80)/2 = 50°

x+y=180
(x-y)/2=40

一个130 一个50

Answer 3

x+y=180
(x-y)/2=40

一个130 一个50