题目

(11)若三点A(2，2)，B(a，0)，C(0，b)(ab≠0)共线，则的值等于___________. 答案：解析：三点A、B、C共线，则∥即（a-2,-2）∥(-2,b-2)      ∴(a-2)(b-2)=4  打开得ab=2(a+b)      ∴连词成句。（1）at / my / look / glue (.)____________________________________________________（2）is / this / book/ his (.)___________________________________________________（3）at / your / point / ruler.___________________________________________________（4）Cshow / me / pencil / your(.)_________________________________________________（5）is / it / Lisa’s / sharpener(.)_________________________________________________