92. Propón y resuelve un problema relacionade el dibujo.

The sum of two numbers is -2 and their product is -15 . Find the two numbers.

Tu madre desea obsequiarte una laptop y una mochila para tu cumpleaños. Visitan a un distribuidor de equipos de cómputo; revisan cinco modelos de laptops (A, B, C, D, E) y 10 modelos de mochilas \( (1,2,3,4,5,6,7,8,9,10) \). ¿De cuántas formas se puede elegir el par de artículos

1) \( (a-5)(a-1) \)

In a game, two standard six-sided dice are thrown. One is painted red Each die is numbered from 1 to 6 . The red die is thrown first followe Three people, Jan, Joe and Jim play the game. If the total is more than 6 , Jan wins. If one of the dice is a 2 or a 3 then Joe wins. If the number on the red die is greater or equal to the number on a) Using any suitable method, show who has the best chance

\( z=\frac{1}{x^{2}+y^{2}-1} \), show that \( x \frac{\partial z}{\partial y}+y \frac{\partial z}{\partial x}=-2 z(1+z) \)