1. Треугольник Пифагора - 5:12:13,
k = 39:3 = 13, x =12*3 = 36 - ответ
k = 52: 13 = 4, x = 12*4 = 48 - ответ
k = 78: 13 = 6, x = 12*6 = 72 - ОТВЕТ
2.
1) а = 10. с = 2*а = 20. С: а = b : y
2) x = 8, a = x :cos60 = x : 0.5 = 2*x = 16, c = 2*a, b= √3/2*8 = 4*√3.
3. sin 30 = 0.5, cos 30 = √3/2, cos 45 = sin 45 = √2/2.
1) x = 3√2 : 0.5 = 6*√2, y = 3√2 * tg60 = √3*3√2 = 3*6 = 18
2) x = 12 : √2/2 = 6√2
3) y = 24*0.5 = 12, x = 24*√3/2 = 12√3