Question

Solve x^2+2x+1=0 by graphing

Answer 1

1. Solutions are − 1 ,2 and  postive 2 and 1 /2 Explanation: When we draw graph of y = x 2 − 2 x − 1 , as a point on x -axis means y = 0 , intercepts on x -axis, give the solution of equation x 2 − 2 x − 1 = 0 Now, if x = 2 , y = − 1 if x = 0 , y = − 1 if x = − 2 , y = 7 if x = 1 , y = − 2 if x = 3 , y = 2 and if x = − 3 , y = 14 So joining points { ( 2 , − 1 ) , ( 0 , − 1 ) , ( − 2 , 7 ) , ( 1 , − 2 ) , ( 3 , 2 ) , ( − 3 , 14 ) } we get the graph graph{x^2-2x-1 [-10, 10, -5, 5]} It shows that intercepts on x -axis are − 1 2 and 2 1 2 Hence, these are the solutions.