Question

determinați nr intregi nenule a si b pentru care
a×b=5×(a+b)
pls ajutooor

Answer 1

$ab=5a+5b\\ \\ a(b-5)=5b\Rightarrow~a=b*\frac{5}{b-5} \Rightarrow~b-5\in~D_5=\{1,-1,5,-5\} \\ \\ \Rightarrow~b=\{6,4,10,0\}\\ \\ \Rightarrow~a=\{30,-20,0,10\}$