初中數(shù)學(xué)資源網(wǎng)變化的魚第五章位置的確定初中數(shù)學(xué)資源網(wǎng)123456780–1–2–3–4–512349105在直角坐標(biāo)系中描出以下各點(diǎn)：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)并用線段依次連接,看一看是什么圖案.

yx初中數(shù)學(xué)資源網(wǎng)123456780–1–2–3–4–512349105圖中的魚是將坐標(biāo)為：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的點(diǎn)用線段依次連接而成的縱坐標(biāo)保持不變,將各坐標(biāo)的橫坐標(biāo)變成原來的2倍會(huì)得到什么？則原坐標(biāo)變?yōu)椋?0,0)(10,4)(6,0)(10,1)(10,-1)(6,0)(8,-2)(0,0)yx初中數(shù)學(xué)資源網(wǎng)123456780–1–2–3–4–512349105圖中的魚是將坐標(biāo)為：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的點(diǎn)用線段依次連接而成的縱坐標(biāo)保持不變，將各坐標(biāo)的橫坐標(biāo)變成原來的2倍會(huì)得到什么？則原坐標(biāo)變?yōu)椋?0,0)(10,4)(6,0)(10,1)(10,-1)(6,0)(8,-2)(0,0)yx原圖形被橫向拉伸2倍初中數(shù)學(xué)資源網(wǎng)123456780–1–2–3–4–512349105圖中的魚是將坐標(biāo)為：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的點(diǎn)用線段依次連接而成的縱坐標(biāo)保持不變,將各坐標(biāo)的橫坐標(biāo)變成原來的1/2，圖形會(huì)怎么變？則原坐標(biāo)變?yōu)椋?0，0)(2.5，4)(1.5，0)(2.5，1)(2.5，-1)(1.5，0)(4，-2)(0，0)yx原圖形被橫向壓縮1/2初中數(shù)學(xué)資源網(wǎng)123456780–1–2–3–4–512349105圖中的魚是將坐標(biāo)為：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的點(diǎn)用線段依次連接而成的則坐標(biāo)變?yōu)?3,0)(8,4)(6,0)(8,1)(8,-1)(6,0)(7,-2)(3,0)

縱坐標(biāo)保持不變,將各坐標(biāo)的橫坐標(biāo)+3又會(huì)怎樣？yx原圖形被橫向（向右）平移3個(gè)單位初中數(shù)學(xué)資源網(wǎng)123456780–1–2–3–4–512349105圖中的魚是將坐標(biāo)為：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的點(diǎn)用線段依次連接而成的則坐標(biāo)變?yōu)椋?-2,0)(3,4)(1,0)(3,1)(3,-1)(1,0)(2,-2)(-2,0)

縱坐標(biāo)保持不變,將各坐標(biāo)的橫坐標(biāo)-2,圖案會(huì)變成什么樣？yx-1-2猜一猜原圖形被向左平移2個(gè)單位初中數(shù)學(xué)資源網(wǎng)123456780–1–2–3–4–512349105圖中的魚是將坐標(biāo)為：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的點(diǎn)用線段依次連接而成的yx想一想將各坐標(biāo)的縱坐標(biāo)保持不變,橫坐標(biāo)都乘以-1,圖形會(huì)變成什么樣？則原坐標(biāo)變?yōu)?0,0)(-5,4)(-3,0)(-5,1)(-5,-1)(-3,0)(-4,-2)(0,0)初中數(shù)學(xué)資源網(wǎng)12345-1-2-30–1–2–3–4–51234-4-55圖中的魚是將坐標(biāo)為：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的點(diǎn)用線段依次連接而成的則原坐標(biāo)變?yōu)?0,0)(-5,4)(-3,0)(-5,1)(-5,-1)(-3,0)(-4,-2)(0,0)將各坐標(biāo)的縱坐標(biāo)保持不變,橫坐標(biāo)都乘以-1,圖形會(huì)變成什么樣？yx想一想與原圖形關(guān)于y軸對稱初中數(shù)學(xué)資源網(wǎng)–4123456780–1–2–361234578910xy圖中的魚是將坐標(biāo)為：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的點(diǎn)用線段依次連接而成的如果橫坐標(biāo)保持不變，縱坐標(biāo)變成原來的2倍，那么所得圖案又會(huì)發(fā)生什么變化?猜一猜原圖形被縱向拉伸2倍初中數(shù)學(xué)資源網(wǎng)–4123456780–1–2–361234578910xy圖中的魚是將坐標(biāo)為：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的點(diǎn)用線段依次連接而成的如果橫坐標(biāo)保持不變，縱坐標(biāo)變成原來的?，那么所得圖案又會(huì)發(fā)生什么變化?猜一猜原圖形被縱向壓縮1/2初中數(shù)學(xué)資源網(wǎng)123456780–1–2–3–4–512345圖中的魚是將坐標(biāo)為：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的點(diǎn)用線段依次連接而成的橫坐標(biāo)保持不變,將各坐標(biāo)的縱坐標(biāo)都+2,則原圖型變?yōu)槭裁礃樱縴x猜一猜原圖形被縱向（向上）平移2個(gè)單位初中數(shù)學(xué)資源網(wǎng)123456780–1–2–3–4–512345圖中的魚是將坐標(biāo)為：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的點(diǎn)用線段依次連接而成的橫坐標(biāo)保持不變,將各坐標(biāo)的縱坐標(biāo)都-1,則原圖型變?yōu)槭裁礃?？yx猜一猜原圖形被向下平移1個(gè)單位初中數(shù)學(xué)資源網(wǎng)123456780–1–2–3–4–512345圖中的魚是將坐標(biāo)為：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的點(diǎn)用線段依次連接而成的將各坐標(biāo)的縱坐標(biāo)都乘以-1,橫坐標(biāo)保持不變,則圖形怎么變化？原坐標(biāo)變?yōu)?0,0)(5,-4)(3,0)(5,-1)(5,1)(3,0)(4,2)(0,0)yx猜一猜與原圖形關(guān)于x軸對稱初中數(shù)學(xué)資源網(wǎng)–4123456780–1–2–361234578910xy1.圖中的魚是將坐標(biāo)為：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的點(diǎn)用線段依次連接而成的如果橫坐標(biāo)與縱坐標(biāo)同時(shí)乘以2，那么所得圖案又會(huì)發(fā)生什么變化?

原坐標(biāo)變?yōu)椋?0,0)(10,8)(6,0)(10,2)(10,-2)(6,0)(8,-4)(0,0）原圖形被橫向、縱向各拉伸2倍原圖形的形狀沒變，面積是原來的4倍。初中數(shù)學(xué)資源網(wǎng)–5圖中的魚是將坐標(biāo)為：(0,0)(5,4)(3,0)(5,1)(5,-1)(3,0)(4,-2)(0,0)的點(diǎn)用線段依次連接而成的將各坐標(biāo)的縱坐標(biāo)與橫坐標(biāo)都乘以-1,圖形會(huì)變成什么樣？yx234510–1–2–3–412345–1–2–3–4–5原坐標(biāo)變?yōu)?0,0)(-5，-4)(-3,0)(-5,-1)(-5,1)(-3,0)(-4,2)(0,0)猜想與原圖形關(guān)于原點(diǎn)中心對稱初中數(shù)學(xué)資源網(wǎng)一、平移1.縱坐標(biāo)不變，橫坐標(biāo)分別增加（減少）a個(gè)單位時(shí)，圖形

平移a個(gè)單位；2.橫坐標(biāo)不變，縱坐標(biāo)分別增加（減少）a個(gè)單位時(shí)，圖形

平移a個(gè)單位；向右（向左）向上（向下）二、伸長（壓縮）3.縱坐標(biāo)不變，橫坐標(biāo)分別變?yōu)樵瓉淼腶倍，圖形

為原來的a倍（a>1）4.橫坐標(biāo)不變，縱坐標(biāo)分別變?yōu)樵瓉淼腶倍，圖形

為原來的a倍（a>1）5.橫坐標(biāo)與縱坐標(biāo)同時(shí)變?yōu)樵瓉淼腶倍，圖形

為原來的a倍(a>1)…伸長或圖形橫向縮短為原來的a倍橫向(0<a<1)。

伸長縱向或圖形縱向縮短為原來的a倍（0<a<1）?？v、橫向同時(shí)伸長初中數(shù)學(xué)資源網(wǎng)三、軸對稱6.縱坐標(biāo)不變，橫坐標(biāo)分別乘-1，所得圖形與原圖形關(guān)于

；7.橫坐標(biāo)不變，縱坐標(biāo)分別乘-1，所得圖形與原圖形關(guān)于

；四、中心對稱8.橫坐標(biāo)與縱坐標(biāo)都乘-1，所得圖形與原圖形關(guān)于

.中心對稱。Y軸對稱X軸對稱原點(diǎn)初中數(shù)學(xué)資源網(wǎng)123410432–2–1–1–2–3–4–3–4123410432–2–1–1–2–3–4–3–4練一練與左圖三角形相比，右圖中的三角形發(fā)生了怎樣變化。右圖中的直角三角形頂點(diǎn)的坐標(biāo)發(fā)生怎樣變化。初中數(shù)學(xué)資源網(wǎng)123410432–2–1–1–2–3–4–3–4123410432–2–1–1–2–3–4–3–4練一練與左圖三角形相比，右圖中的三角形發(fā)生了怎樣變化。右圖中的直角三角形頂點(diǎn)的坐標(biāo)發(fā)生怎樣變化。初中數(shù)學(xué)資源網(wǎng)123410432–2–1–1–2–3–4–3–4123410432–2–1–1–2–3–4–3–4練一練與左圖三角形相比，右圖中的三角形發(fā)生了怎樣變化。右圖中的直角三角形頂點(diǎn)的坐標(biāo)發(fā)生怎樣變化。初中數(shù)學(xué)資源網(wǎng)123410432–2–1–1–2–3–4–3–4123410432–2–1–1–2–3–4–3–4練一練與左圖三角形相比，右圖中的三角形發(fā)生了怎樣變化。右圖中的直角三角形頂點(diǎn)的坐標(biāo)發(fā)生怎樣變化。初中數(shù)學(xué)資源網(wǎng)123410432–2–1