(1) ∠x を求めなさい.
75° A x B 29° C 135° D E F |
(2) ∠x を求めなさい.
x A 32° B 30° C 117° D E |
(3) ∠x を求めなさい.
62° 42° 54° x |
(4) ∠x を求めなさい.
55° A x B 38° C 130° D E F |
(1) ∠x を求めなさい.
75° A x B 29° C 135° D E F ∠CFB = 75 + 29 = 104 ∠BDCは△BDFの頂点Dにおける外角だから∠BDC = ∠B+∠CFB ∠B = ∠x = ∠BDC − ∠CFB = 31 |
(2) ∠x を求めなさい.
x A 32° B 30° C 117° D E よって,∠CED = ∠BDC − ∠C = 117 − 30 = 87 ∠CEDは△ABEの頂点Eにおける外角だから∠CED = ∠A+∠B ∠CED = ∠x + ∠B = 87 よって,∠x = 55 |
(3) ∠x を求めなさい.
62° 42° 54° x 対頂角 = 180−(∠x+62) = 180−(42+54) ∠x = 34 |
(4) ∠x を求めなさい.
55° A x B 38° C 130° D E F ∠CFB = 55 + 38 = 93 ∠BDCは△BDFの頂点Dにおける外角だから∠BDC = ∠B+∠CFB ∠B = ∠x = ∠BDC − ∠CFB = 37 |