Odpowiedź:
Córka: 12 lat
Mama: 40 lat
Szczegółowe wyjaśnienie:
x - córka
y - mama
[tex]\left \{ {{5(x-5)=y-5} \atop {x+10+y+10=72}} \right.[/tex]
[tex]\left \{ {{y=5x-20} \atop {x=52-y}} \right.[/tex]
[tex]\left \{ {{y=5x-20} \atop {x=52-5x+20}} \right.[/tex]
[tex]\left \{ {{y=5x-20} \atop {6x=72}} \right.[/tex]
[tex]\left \{ {{y=5x-20} \atop {x=12}} \right.[/tex]
[tex]\left \{ {{y=40} \atop {x=12}} \right.[/tex]