1. 3x + 7x + 2x = 180
12x = 180
x = 15
15 ·3 = 45
15 ·2 = 30
15 · 7= 105
Ответ: R = 45
P = 105
Q = 30
2.
x - K
2x + (2x - 20) + x = 180
2x + 2x - 20 + x = 180
5x = 200
x = 40
40 · 2 = 80
80 - 20 = 60
Ответ: K = 40
N = 60
M = 80
3. x - S
1.5x + 1.5x + x = 180
4x = 180
x = 45
P = R = 67.5
Ответ: S = 45
P = R = 67.5