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确定一次函数y=kx+b(k≠0)中的k的值,是中考中的一个亮点.有关的题型灵活新颖,富有趣味性和探索性.下面就结合近年中考题向同学们作一介绍.一、图象过点,点的某一个坐标是k,确定k的值例1(2011年·芜湖)已知直线y=kx+b经过点(k,3)和(1,k),则k的值为().A.3~/(1/2) B.±3~/(1/2) C.2~/(1/2) D.±2~/(1/2)分析:图象过点的意义是解题的突破口.其实质是点的坐标满足函数的解析式.将点的坐标代入解析式,可将问题转化成方程组问题.解:因为直线y=kx+b经过点(k,3)和(1,k),所
Determine the value of k in a function y = kx + b (k ≠ 0), is a bright spot in the test. Related topics in a flexible, interesting and exploratory. First, the image is too point, the point of a coordinate is k, to determine the value of k Example 1 (2011 Wuhu) known line y = kx + b after the point (k, 3) and ), The value of k is () .A.3 ~ / (1/2) B. ± 3 ~ / (1/2) C.2 ~ / (1/2) D. ± 2 ~ / (1 / 2) Analysis: the meaning of the image is too point of solution to the problem of breach. Its essence is the point coordinates to meet the analytical function of the function. Point coordinates into the analytic formula can be converted into equations problem. Solution: Because the straight line y = kx + b passes through points (k, 3) and (1, k)