275+(300-a×26):8=306

Răspuns :

275+(300-a×26):8=306
(300-a×26):8=306-275
(300-a×26):8=31
300-a×26=31×8
300-a×26=248
a×26=300-248
a×26=52
a=52:26
a=2


Verificare

275+(300-2×26):8=
=275+(300-52):8=
=275+248:8=
=275+31=
=306 (adevarat )
275+(300-a×26):8=306
(300-a×26):8=31
300-a×26=248
a×26=52
a=2