Question

11．方程x+3y=-8的負(fù)整數(shù)解有2組，分別是$\left\{\begin{array}{l}{x=-5}\\{y=-1}\end{array}\right.$，$\left\{\begin{array}{l}{x=-2}\\{y=-2}\end{array}\right.$．

Answer 1

分析 把y看做已知數(shù)表示出x，即可確定出負(fù)整數(shù)解．

解答 解：方程x+3y=-8，
解得：x=-3y-8，
當(dāng)y=-1時(shí)，x=-5；y=-2時(shí)，x=-2；
則方程的負(fù)整數(shù)解有2組，分別為$\left\{\begin{array}{l}{x=-5}\\{y=-1}\end{array}\right.$，$\left\{\begin{array}{l}{x=-2}\\{y=-2}\end{array}\right.$．
故答案為：2；$\left\{\begin{array}{l}{x=-5}\\{y=-1}\end{array}\right.$，$\left\{\begin{array}{l}{x=-2}\\{y=-2}\end{array}\right.$．

點(diǎn)評(píng) 此題考查了解二元一次方程，解題的關(guān)鍵是將y看做已知數(shù)求出x．