Question

11. ZAOB = 90º. По рисунку 11 найдите ZАОС и ZВОС: a) 6) Al (3x-5)9 (x + 15)° В C (4x + 30) А X В 0 Puc. 11 ALON А (2x+25)° в (3x-35)°​

Answer 1

а)

$3x - 5 + x + 15 = 90 \\ 4x = 90 - 10 \\ 4x = 80 \\ x = 80 \div 4 \\ x = 20 \\ 3x - 5 = 3 \times 20 - 5 = 60 - 5 = 55 \\ x + 15 = 20 + 15 = 35$

<AOC = 55°

<BOC = 35°

б)

$4x + 30 + x = 90 \\ 5x = 90 - 30 \\ 5x = 60 \\ x = 60 \div 5 \\ x= 12 \\ 4x + 30 = 4 \times 12 + 30 = \\ 48 + 30 = 78$

<AOC = 12°

<BOC = 78°

в)

$2x + 25 + 3x - 35 =9 0 \\ 5x = 90 + 10 \\ 5x = 100 \\ x = 100 \div 5 \\ x = 20 \\ 2x + 25 = 2 \times 20 + 25 = 40 + 25 = 65 \\ 3x - 35 = 3 \times 20 - 35 = 60 - 35 = 25$

<AOC = 65°

<BOC = 25°