On the way to the airport, Qi Yi said he wanted to give Yan Yan a gift and then he wrote down an equation in a notebook he was carrying—17·x^2-16|x|y+17y^2=225.
"It's been a while since we solved problems together, I'm gifting you this simple equation. When I'm not in Melbourne, solve it if you're feeling bored," Qi Yi said as he tore the page with the equation from his notebook.
"Okay~ but, it's been so long since I even knew what math was. I feel like even if math still recognized me, I no longer recognize math. I'll give it a try," Yan Yan smiled as she took the paper from Qi Yi.
"Bao Bao, do you think those two have something wrong with their brains? Who gifts a mathematical formula? And what's more, someone's actually happy receiving it," Shen Xi thought the two in the backseat were odd.
"Take a look at it when you're free later, maybe those two, after eating 'P', might want to gift 'farts'," Bao Bao suddenly became curious about the equation Qi Yi wrote.
