Question

Найдите неизвестный член пропорции: 1) -7/8=X/24; 2) 5/-9=10/X; 3) -5/1,2=x/-6; 4) -3,5/4=X/20; 5) -1,9/3=X/15; 6) 4,1/-7=20,5/-y.

Answer 1

-7/8 = x/24

8x = -7 * 24

x = -7 * 24 / 8

x = -7 * 3

x = -21

5/(-9) = 10/x

-9 * 10 = 5x

-90 = 5x

x = -90 / 5

x = -18

-5/1,2 = x/(-6)

1,2x = -6 * (-5)

1,2x = 30

x = 30 / 1,2

x = 300 / 12

x = 25

-3,5/4 = x/20

4x = -3,5 * 20

x = -3,5 * 20 / 4

x = -3,5 * 5

x = -17,5

-1,9/3 = x/15

3x = -1,9 * 15

x = -1,9 * 15 / 3

x = -1,9 * 5

x = -9,5

4,1/(-7) = 20,5/(-y)

-7 * 20,5 = -y * 4,1

-4,1y = -143,5

y = 35