观察分析下列方程：①x+
|
∵由①得，方程的根为：x=1或x=2，
由②得，方程的根为：x=2或x=3，
由③得，方程的根为：x=3或x=4，
∴方程x+
=a+b的根为：x=a或x=b，ab x
∴x+
=2n+4可化为（x-3）+n2+n x-3
=n+（n+1），n(n+1) x-3
∴此方程的根为：x-3=n或x-3=n+1，
即x=n+3或x=n+4．
故答案为：x=n+3或x=n+4．
| 完型填空。 | ||||
| John is a Canadian. He lives in a tall building. He gets up at _1_ every morning. He _2_ home at seven o'clock. And he gets to school at seven forty. He has _3_ classes in the morning and two in the _4_. After school, he likes to play volleyball _5_ his classmates. He goes home at five thirty _6_. He and his _7_ have dinner _8_ home. _9_ he does his homework. He goes to _10_ at around nine thirty. What a busy day! | ||||
|