.:Math Homework Need Help:. Please?

Question

PLEASE HELP ME WITH MY HOMEWORK I SERIOUSLY DONT GET IT. please show ur work :D

Pierre was born in the twentieth century and will be x years old in the year x2(x to the second power). In what year was Pierre Born?

Answer 1

NO.... this is how you do this problem...

The twentieth century means... the year 19_ _ something...

So that means that in order for x^2 to fall in the 1900-2000 range.... possible x's would be....

Well... if x = 40, then x^2 = year 1600

And if x = 50, then x^2 = year 2500

So now at least you know that x is between 40 and 50

If x = 45, then x^2 = 2025

Hmmm.... that's pretty close to the 1900-2000 that we are looking for. So he will be 45 in the year 2025. So what happens if you subtract 45 years to get the year he was born in?

2025 - 45 = 1980

He was born in 1980. This is your answer because 1980 is in the 20th century.

Hope this makes sense. It was a hard one, even for me!!! Thanks for making me think! :o) LOL That's why I gave you a yellow star. GOOD thinking question!!!

Answer 2

First off the twentieth century is 1900 to 1999 which may not be important, but is good to know.

Assume that Pierre was born in year y then

x^2 - y = x

if I understand your equation correctly. Just for fun what happens if we let y = 1900 then you get

x^2 -x -1900 = 0

and x = 44.09 and -43.09

There appear to be solutions for many years in the 20th century.

Maybe I don't have the problem correctly?

Answer 3

well 20th century means from 1900 - 1999, and unless he's immortal thats impossible because his age ranges from 3610000 to 3996001

Answer 4

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Answer 5

i dont think this gives enough information