How do you solve the equation $x^2-2x-1=0$ by graphing?

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Answer 1 · 2016-12-20T17:17:51

Solutions are $-1/2$ and $2 1/2$

When we draw graph of $y=x^2-2x-1$ ,

as a point on $x$ -axis means $y=0$ ,

intercepts on $x$ -axis, give the solution of equation $x^2-2x-1=0$

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.

How do you solve the equation x^2-2x-1=0x^2-2x-1=0 by graphing?