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【332193】【推荐】27.3 位似-同步练习(1)A

时间:2025-01-21 12:27:15 作者: 字数:2578字
简介:

27.3 位似

基础梳理

1.如果两个多边形不仅 ,而且对应顶点的连线 ,那么这样的两个图形叫做

,这 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 点叫做 .对应边的比叫做 ,位似比等于 .

2.一般的在平面坐标系中,如果以原点为位似中心,画出一个与原图形位似的图形,使他与 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 原图形的相似比为k,那么与原图形上的点(x, <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> y)对应的位似图形上的点的坐标为 .

【位似求 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 坐标问题】

1.如图,线段AB两个端点的坐标分别为A(66)B(82),以原点O为位似中心,在第一象限内将线段AB缩小为原来的 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 后得到线段CD,则端点C的坐标为 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> ( )

A(33) B(43) C(31) D <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> (41)

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a>  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 组合 707

2.如图,已知点 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> A和点B是直线 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 的两点,A点坐标( <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 2 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> )若AB=5,则点B的坐标是 [来源:&&Z&X&X&K]

3.如图,正方形OABC与正方形ODEF是位似图形,点O为位似中心,[来源:,,Z,X,X,K]

相似比为1 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> ,点 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> A的坐标为(01),则点E的坐标是

【画位似图形】

4.13×13的网格中,已知△ABC <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 和点M(12)

(1)以点M为位似中心,位似比为2,画出△ABC的位似图形△A′B′C′

(2)写出△A′B′C <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a>的各顶点坐标.

组合 684

5.如图,在边长为1个单位长度的小正方形组成的网格中,给出了格点△ABC(顶点是网格线的交点).

1)将△ABC向上平移3个单位得到△A1B1C1,请画出△A1B1C1

2)请画出一个格点△A2B2C2,使△A2B2C2∽△A1B1C1,且相似比不为1

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a>

6.如图,在平面直角坐标系x <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> oy中,△ABC三个顶点坐标分别为A(-24),B(-2,1),C(-5,2

请画出△ABC关于x轴对称的△A1B1C1

将△A1B1C1的三个顶点的横坐标与纵坐标同时乘以-2,得到对应的点A2B2C2 ,请画出△A2B2C2

求△A1B1C1与△A2B2C2的面积比,即 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> =________(不写解答过程,直接写出结果). [来源:Zxxk.Com]

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a>

7.如图,在平面直角坐标系中, <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 的三个顶点坐标分别为 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> ( <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 1) <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> ( <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 4) <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> ( <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 2)

1)画出 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 关于 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 轴对称的图形 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> ,并直接写出 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 点坐标;

2)以 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 原点 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 为位似中心,位似比为1:2,在 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 轴的左侧,画出 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 放大后的图形 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> ,并直接写出 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 点坐标;[来源:学科网ZXXK]

3)如果点 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> ( <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a>  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> )在线段 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a>  <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 上,请直 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 接写出经过(2)的变化后 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 的对应点 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a> 的坐标.[来源:Zxxk.Com]

 <a href="/tags/48/" title="练习" class="c1" target="_blank">练习</a> <a href="/tags/50/" title="同步" class="c1" target="_blank">同步</a> <a href="/tags/145/" title="推荐" class="c1" target="_blank">推荐</a>