Marinada '21

[lang=hr] Stekavši znanje o perspektivi slikar ga je krenuo primijeniti. Sada slikar želi naslikati curu i njenog dečka. Cura je visoka $160 cm$, a dečko $200 cm$. Curina glava je $25 cm$ duga (od brade do vrha glave), a dečkova $29 cm$. Ako je staklo ponovno u $XZ$ ravnini, a slikarovo oko u točki $(0 cm ,20 cm ,50 cm)$ i ako su tabani cure na točki $(0 cm, -50 cm, 0 cm)$ te ona gleda prema slikaru, koliko centimetara iza nje treba stajati dečko da na slici izgleda kao da mu brada leži tik na njenoj glavi. [/lang] [lang=en] Having learnt about perspective the artist set out to use it. The artist now wants to draw a girl and her boyfriend. The girl has a total height of $160 cm$, and the boy has total a height of $200 cm$ . The girl's head from the chin up is $25 cm$ and the boy's is $29 cm$. If the pane of glass is once again positioned in the $XZ$ plane, the artist's eye is at $(0 cm ,20 cm ,50 cm)$ , the girl's feet are at $(0 cm, -50 cm, 0 cm)$ and she is facing the artist. How many centimeters behind her must the boy stand in order for it to appear as if his chin is resting on the top of her head? [/lang]