SOLUTION: how do i solve 8x^2-11x-11=0 using the graphical method

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Question 949449: how do i solve 8x^2-11x-11=0 using the graphical method
Found 2 solutions by Theo, MathLover1:
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
here's the graph.
the points you are interested in are the points where the graph crosses the x-axis.

$$$

it helps to used a graphing software that identifies the intersection points for you.

otherwise, you are left to the resolution of the grpah and you eyesight to narrow the result down.

most of the time, you won't be able to get to within a tenth of a unit that way.

having the computer calculate it for you is the way to go.


Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
8x%5E2-11x-11=0...here you have a parabola (function is of degree 2)
to use the graphical method, choose several values for variable x, calculate y, you will get the coordinates of the points that lie on this parabola
x|y
-2|43 ->8x%5E2-11x-11=y->8%28-2%29%5E2-11%28-2%29-11=y->32%2B22-11=y->43=y
-1|8 ->8%28-1%29%5E2-11%28-1%29-11=y->8%2B11-11=y->8=y
0|-11 ->8%280%29%5E2-11%280%29-11=y->0%2B0-11=y->-11=y
1|-14 ->8%281%29%5E2-11%281%29-11=y->8-11-11=y->-14=y
2|-1 ->8%282%29%5E2-11%282%29-11=y->32-22-11=y->-1=y
3|-1 ->8%283%29%5E2-11%283%29-11=y->72-33-11=y->28=y
now, plot these points and draw a line through