Răspuns :
[tex] a^{2}- b^{2} =39<=>(a+b)(a-b)=39<=>(a+b)*3=39=> \\ \\ =>a+b=13.[/tex]
⇒ (a+b)(a-b)=39 ⇒ avem posibilitatile: 39=1x39=39x1=3x13=13x3
pt. a > b eliminam perechile care nu indeplinesc conditia ,
ramane (a+b)(a-b)=39=39 x 1 = 13 x 3
↓
a+b =39 sau a+b=13
↓ ↓
a=20 ; b=19 a=8 ; b=5
pt. a > b eliminam perechile care nu indeplinesc conditia ,
ramane (a+b)(a-b)=39=39 x 1 = 13 x 3
↓
a+b =39 sau a+b=13
↓ ↓
a=20 ; b=19 a=8 ; b=5