Answer :
[tex]Use:log_ab+log_ac=log_a(b+c)\\\\=================================\\\\log_57+log_53=log_5(7+3)=log_510[/tex]
log. 5 (7) + log.5 (3) = log. 5 (7*3)=log. 5 (21)
the formula is
log. a (x) + log. a (y)= log.a (x*y)
the formula is
log. a (x) + log. a (y)= log.a (x*y)