Question

решите пожалуйста токо нечётные номера​

Answer 1

1) ∠a₁b₁ = ∠ab = 120°

∠ab₁ = (360-120×2)÷2 = 60°

3) ∠mn = 360 - (∠mn₁ +∠m₁n₁ +∠m₁n) = 360 - 240 = 120°

5) ∠1 = ∠3; ∠2 = ∠4.

Пусть х - ∠1 и ∠3, а y - ∠2 и ∠4. Тогда:

$\left \{ {{2(x+x)=y+y} \atop {x+y=180}} \right.   \left \{ {{4x=2y} \atop {x+y=180}} \right.   \left \{ {{y=2x} \atop {x+2x=180}} \right.   \left \{ {{y=2x} \atop {3x=180}} \right.   \left \{ {{y=2*60} \atop {x=60}} \right. \left \{ {{y=120} \atop {x=60}} \right.$

∠1 = ∠3 = 60°

∠2=∠4 = 120°

7) Пусть ∠1 - х, а ∠2 и ∠3 - y. Тогда:

$\left \{ {{x=y+y} \atop {x+y=180}} \right. \left \{ {{x=2y} \atop {2y+y=180}} \right. \left \{ {{x=60*2} \atop {y=60}} \right. \left \{ {{x=120} \atop {y=60}} \right.$

∠1=120°

∠2, ∠3 =60°