hopa just add

51 - 39=	12
43 - 28=	25

51 - 27=	24
34 - 19=	15
342 - 168	174
292 - 168	124
532 - 318	214

Question	Photo of your working out.
82 - 28	28 + ? = 82
51 - 39=	12
43 - 28=	25
51 - 27=	24
34 - 19=	15
342 - 168	174
292 - 168	124
532 - 318	214
422 - 257	165