Tolong bantu jawab ya kak Pakek caranya #maksih...

k = image/object

1. let QR be the image and ST be the object.
2. let PQ be the image and PS be the object.

so,
k = 16/12 and k = (2x + 3 + 8)/(2x + 3)

it will be like this.
16/12 = (2x + 11)/(2x + 3)
8x + 12 = 6x + 33
2x = 21
x = 21/2