Х - 8/15 х = 4 1/5 х= ?

Question

Х - 8/15 х = 4 1/5
х= ?

Answer 1

Х(1-8/15)=21/5
х*7/15=63/15
х=63/7=9
Ответ х=9

Answer 2

Х-8/15Х=21/5
15/15Х-8/15Х=21/5
7/15Х=21/5
Х=21/5:7/15=21/5 х 15/7=3 х 3
Х=9