Răspuns :
[tex]a-b=22 \to \boxed{a=22+b}\\ a+b=42 \\ \\22+b+b=42 \\ 22+2b=42 \\ 2b=42-22 \\ 2b=20\\b=20:2\\ \\\boxed{\boxed{b=10}} \\ \\ a+10=42 \\ a=42-10 \\ \\ \boxed{\boxed{a=32}} \\ \\ \boxed{Verificare: 10+32=42}[/tex]
[tex] \left \{ {{a-b=22} \atop {a+b=42}} \right. [/tex] ⇒ [tex] \left \{ {{a=22+b} \atop {a+b=42}} \right. [/tex] ⇒ [tex] \left \{ {{a=22+b} \atop {22+b+b=42}} \right. [/tex] ⇒ [tex] \left \{ {{a=22+b} \atop {2b=42-22}} \right. [/tex] ⇒ [tex] \left \{ {{a=22+b} \atop {b= \frac{20}{2} }} \right. [/tex] ⇒ [tex] \left \{ {{a=22+10} \atop {b=10}} \right. [/tex][tex] \left \{ {{a=32} \atop {b=10}} \right. [/tex]