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3 years ago

Explain how you know that x^2-8x+20 is always positive. Please help.

Mathematics

1 answer:

IRISSAK [1]3 years ago

4 0

Answer:

if you rearrange to complete the square, you get (x^2-4)^2 +4

and seeing as anything squared will always be positive or zero, the lowest possible value for (x^2-4)^2 is 0, when x = 4

and 0 + 4 = 4, which is greater than 0, so positive

Step-by-step explanation:

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3 years ago

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Step-by-step explanation:

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2 years ago

Read 2 more answers