The sum of the square of a positive number and the square of 2 more than the number is 202. What is the? number?

Mathematics

1 answer:

ehidna [41]4 years ago

3 0

Answer:

x^2 + (x + 2)^2 = 202

x^2 + x^2 + 4x + 4 = 202

2x^2 + 4x + 4 = 202

2x^2 + 4x - 198 = 0

x^2 + 2x - 99 = 0

x = -2/2 ± √((2/2)^2 - (-99))

x = 9 or x = -11

-11 is not a positive number so the number is 9.

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tensa zangetsu [6.8K]

First computer takes x min. For 1 min it does 1/x part of work.

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