Question

47=8+2а21

5/12=3044+7а.

Answer 1

1). 4/7=(8+2а)/21
84=56+14а
84-56=14а
28=14а
а=28/14=2
а=2

2) 5/12=30/(44+7а)
220+35а=360
35а=360-220
35а=140
а=140/35
а=4