求助PREP DS on the number line 三题

13.   1067-!-item-!-187;#058&000618

Is x to the right of -5 on the number line?

(1) x is to the right of -7 on the number line.

(2) x is between -4 and -3 on the number line.

14.   1121-!-item-!-187;#058&000619

Is y between -2 and 1 on the number line?

(1) y is to the right of -1 on the number line.

(2) y is to the left of 2 on the number line.

15.   1175-!-item-!-187;#058&000621

Is r to the right of -6 on the number line?

(1) r is between -4 and -1 on the number line.

(2) r is between -3 and 1 on the number line.

居然三道连错,

求教思路,谢谢!

第一个是B  条件2已经给出了范围 应该就能确定和-5的关系了

第2个是E吧 要确定-2<x<1 只知道-1<x<2 是确定不了的把

第3个D吧... 要比-6大 那-4到-1  -3到1都能确定哦

也就是说这这三道题等价于

13. X>-5?

1. X>-7

2. -4<X<-3

14.-2<Y<1?

1.Y>-1

2.Y<2

15.R>-6?

1.-4<X<-1

2.-3<X<1

原来如此,谢谢