SOLUTION: x2-8x>0 solve and write th solutino set in interal notation

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Question 442682: x2-8x>0 solve and write th solutino set in interal notation
Answer by swincher4391(1107) About Me  (Show Source):
You can put this solution on YOUR website!
x^2-8x>0
Solve x^2-8x = 0
x(x-8) = 0
x =0 , x =8
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Locate a point that is less than 0:
Let's choose -1. (-1)^2 + 8 = 9 POSITIVE. Remember this.
Choose a point between 0 and 8.
Let's choose 1. 1^1 - 8 = -7 NEGATIVE.
Choose a point greater than 8, choose 9.
9^2 - 8(9) = 9 POSITIVE. Remember this.
Find where y is positive: When y<0 and when y>8.
Thus our answer is in interval notation (-infinity,0) U (8,infinity)
U means the union of.