tolong dijawab yah, lgi butuh

a. x/4 = 5/12 (caranya adalah dgn dikali silang)
x × 12 = 5 × 4
12x = 20
x = 20/12 (sama2 dibagi 4) = 5/3

b. x/9 = 12/8 (caranya adalah dgn dikali silang)
x × 8 = 9 × 12
8x = 108
x 108/8 (sama2 dibagi 4) = 27/2

c. 15/(x + 4) = 20/16 (caranya adalah dgn dikali silang)
15 × 16 = 20(x + 4)
240 = 20x + 80
240 - 80 = 20x
160 = 20x
160/20 = x
8 = x

2a.
x/4 = 5/12
12x = 5 × 4
12x = 20
x = 20/12
x = 5/3
x = 1 2/3

b.
x/9 = 12/8
8x = 12 × 9
8x = 108
x = 108/8
x = 27/2
x = 13 1/2


c.
15/(x + 4) = 20/16
15 × 16 = 20(x + 4)
240 = 20x + 80
20x = 240 - 80
20x = 160
x = 160/20
x = 8