tolong dong please makasih

(12-x) / (9-4) = 12 / 9
(12-x) / 5 = 4/3
12-x = 4/3 x 5
12 - x = 20/3
x = 12 - 20/3
x = 12 - 6 2/3
x = 5 1/3 cm

y / 9 = 5/5
y / 9 = 1
y = 9 cm