《一次函數(shù)與二元一次方程的關(guān)系》課件

21.5一次函數(shù)與二元一次方程的關(guān)系/article_13608.html/article_12191.html/article_11757.html/article_11759.html/article_11766.html/article_11768.html/article_14419.html/article_14582.html/article_14217.html/article_14422.html/article_14220.html/article_15875.html/article_15931.html/article_15806.html/article_15803.html/article_14866.html/article_12535.html/article_12728.html/article_12538.html/article_12762.html/article_12763.html/article_12552.html/article_12798.html/article_12770.html/article_12774.html/article_12371.html/article_12527.html/article_12532.html/article_12533.html/article_12370.html/article_12534.html/article_12775.html/article_12771.html/article_12529.html/article_12765.html/article_12539.html/article_12553.html/article_12772.html/article_12785.html/article_12551.html/article_12767.html/article_12530.html/article_12542.html/article_12549.html/article_12727.html/article_12768.html/article_12769.html/article_12797.html/article_14264.html/article_14293.html/article_14101.html/article_13812.html/article_14102.html/bdsshz/question/13703420.html/bdsshz/question/18764700.html/bdsshz/question/20998779.html/bdsshz/question/21000094.html/bdsshz/question/21114780.html/bdsshz/question/21128632.html/bdsshz/question/21135733.html/bdsshz/question/21151920.html/bdsshz/question/21168463.html/bdsshz/question/21168604.html/bdsshz/question/21387399.html/bdsshz/question/27734824.html/bdsshz/question/31843460.html/bdsshz/question/31930107.html/bdsshz/question/20998344.html/bdsshz/question/34918420.html/bdsshz/question/40630158.html/bdsshz/question/40739189.html/bdsshz/question/40629900.html/bdsshz/question/44390594.html/bdsshz/question/47267179.html/bdsshz/question/52642063.html/bdsshz/question/1105039.html/bdsshz/question/11289510.html/bdsshz/question/13200064.html/bdsshz/question/13356970.html/bdsshz/question/13691868.html/bdsshz/question/14027053.html/bdsshz/question/14594997.html/bdsshz/question/28106624.html/bdsshz/question/14924576.html/bdsshz/question/1520822.html/bdsshz/question/15653394.html/bdsshz/question/17133870.html/bdsshz/question/17853533.html/bdsshz/question/18182535.html/bdsshz/question/18306676.html/bdsshz/question/18315310.html/bdsshz/question/18901787.html/bdsshz/question/20316457.html/bdsshz/question/20740399.html/bdsshz/question/20769717.html/bdsshz/question/20940845.html/bdsshz/question/20980408.html/bdsshz/question/20983232.html/bdsshz/question/21005498.html/bdsshz/question/21091943.html/bdsshz/question/21227636.html/bdsshz/question/21244975.html/bdsshz/question/21251706.html/bdsshz/question/21296567.html/bdsshz/question/21317315.html/bdsshz/question/21318560.html/bdsshz/question/21319214.html/bdsshz/question/21368937.html/bdsshz/question/21391523.html/bdsshz/question/21412993.html/bdsshz/question/21421869.html/bdsshz/question/21426461.html/bdsshz/question/21426465.html/bdsshz/question/21447900.html/bdsshz/question/23498773.html/bdsshz/question/23752701.html/bdsshz/question/23920626.html/bdsshz/question/24190473.html/bdsshz/question/24551314.html/bdsshz/question/24944505.html/bdsshz/question/28477729.html/bdsshz/question/29366365.html/bdsshz/question/32137573.html/bdsshz/question/30125129.html/bdsshz/question/30624341.html/bdsshz/question/31887536.html/bdsshz/question/31967056.html/bdsshz/question/31985217.html/bdsshz/question/32096151.html/bdsshz/question/41979664.html/bdsshz/question/40629150.html/bdsshz/question/32096474.html/bdsshz/question/32116505.html/bdsshz/question/38608541.html/bdsshz/question/32185520.html/bdsshz/question/13679506.html/bdsshz/question/32127614.html/bdsshz/question/20983097.html/bdsshz/question/32140269.html/bdsshz/question/32487246.html/bdsshz/question/31893972.html/bdsshz/question/2047204.html/bdsshz/question/32540965.html/bdsshz/question/32077387.html/bdsshz/question/33731358.html/bdsshz/question/32548569.html/bdsshz/question/32548857.html/bdsshz/question/32567996.html/bdsshz/question/32578285.html/bdsshz/question/36387040.html/bdsshz/question/32607904.html/bdsshz/question/32615842.html/bdsshz/question/32853559.html21.5一次函數(shù)與二元一次方程的關(guān)系www.mingyih1學(xué)習(xí)目標(biāo)：1、理解一次函數(shù)與二元一次方程的關(guān)系2、理解一次函數(shù)與二元一次方程組的關(guān)系學(xué)習(xí)目標(biāo)：1、理解一次函數(shù)與二元一次方程的關(guān)系2、理解一次函2探究學(xué)習(xí)一：探究一次函數(shù)與二元一次方程的關(guān)系1、二元一次方程y-x=1有多少個解？你能寫出方程的幾組解嗎?4、把1題中方程的幾組解為坐標(biāo)的點在3題坐標(biāo)系上描出來，你發(fā)現(xiàn)了什么?3、畫出一次函數(shù)y=x+1的圖像。5一次函數(shù)y=x+1的圖像上的點的坐標(biāo)適合二元一次方程y-x=1嗎？2、二元一次方程y-x=1可以寫成一次函數(shù)嗎？探究學(xué)習(xí)一：探究一次函數(shù)與二元一次方程的關(guān)系1、二元一3xy012345-1-2-3-4-512345-167y=x+1xy012345-1-2-3-4-512345-167y=x4

結(jié)論:

以二元一次方程的解為坐標(biāo)的點都在相應(yīng)的函數(shù)圖象上.

反過來,一次函數(shù)圖象上的點的坐標(biāo)都是相應(yīng)的二元一次方程的解.結(jié)論:51、以方程2x-y=1的解為坐標(biāo)的點都在一次函數(shù)

______的圖像上。2、一次函數(shù)y=3x+7的圖像與y軸的交點坐標(biāo)----,且該點的橫坐標(biāo)是方程-2x+by=14的解，則b=----.體驗成功喜悅練一練y=2x-1(0,7)21、以方程2x-y=1的解為坐標(biāo)的點都在一次函6

2、在同一直角坐標(biāo)系中畫出一次函數(shù)y=x+1和y=-x+1的圖像。探究學(xué)習(xí)二：探究一次函數(shù)與二元一次方程組的關(guān)系1、解方程組x+y=1-x+y=12、在同一直角坐標(biāo)系中畫出一次函數(shù)y=x+1和y=7xy012345-1-2-3-4-512345-167y=x+1y=-x+1(0,1)x+y=1-x+y=1是否任意兩個一次函數(shù)的交點坐標(biāo)都是它們所對應(yīng)的二元一次方程組的解？xy012345-1-2-3-4-512345-167y=x8歸納總結(jié):二元一次方程組的解是這兩個方程所對應(yīng)的一次函數(shù)圖像的交點坐標(biāo)。反之，兩個一次函數(shù)圖像的交點坐標(biāo)是這兩個一次函數(shù)所對應(yīng)的二元一次方程組的解。若二元一次方程組無解，那么這兩個方程所對應(yīng)的一次函數(shù)圖像---------。？想一想歸納總結(jié):二元一次方程組的解是這兩個方程所對91、方程組的解是

，由此可知一次函數(shù)

與

的圖像必有一個交點，且交點坐標(biāo)是

。x-y=43x-y=16體驗成功喜悅練一練x=6y=2y=x+4

y=-3x+16(6，2)x-y=43x-y=16體驗成功喜悅練一練x=6y=2y=x102、根據(jù)下列圖象，你能說出它表示哪個方程組的解？這個解是什么？11xyoy=2x-1y=-3x+4練一練2、根據(jù)下列圖象，你能說出它表示哪個方程組的解？這個解是什么112x+y=42x-3y=123、用圖象法解方程組①②解：由①得:由②得:作出圖象：觀察圖象得：交點為(3,-2)∴方程組的解為x=3y=-2xoyy=-2x+4y=2/3x-4練一練2x+y=42x-3y=123、用圖象法解方程組①②解：由①12老師為了教學(xué)，需要在家上網(wǎng)查資料。電信公司

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