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## #1 Help Me ! » Quadratic expression word problem » 2011-05-10 16:30:55

00jwaj
Replies: 1

The cumulative number of car accidents from 2000 to 2010 can be modeled by the quadratic expression C = -43x² + 1376x + 12040 where x=0 corresponds to 2000, x=1 corresponds to 2001 and so on until x=10 corresponds to 2010. Find the number of cumulative car accidents in 2005.
C = -43x² + 1376x + 12040
C = -43(0)² + 1376(0) + 12040
C = 0 + 0 + 12040
C = 12040 accidents in 2000

C = -43x² + 1376x + 12040
C = -43(1)² + 1376(1) + 12040
C = -43 + 1376 + 12040
C = 13373 accidents in 2001

C = -43x² + 1376x + 12040
C = -43(2)² + 1376(2) + 12040
C = -43*4 + 2752 + 12040
C = -52 + 2752 + 12040
C = 14620 accidents in 2002

C = -43x² + 1376x + 12040
C = -43(3)² + 1376(3) + 12040
C = -43*9 + 4128 + 12040
C = -387 + 4128 + 12040
C = 15781 accidents in 2003

C = -43x² + 1376x + 12040
C = -43(4)² + 1376(4) + 12040
C = -43*16 + 5504 + 12040
C = -688 + 5504 + 12040
C = 16856 accidents in 2004

C = -43x² + 1376x + 12040
C = -43(5)² + 1376(4) + 12040
C = -43*15 + 5504 + 12040
C = -688 + 5504 + 12040
C = 18,189 accidents in 2005

I'm going crazy I can't figure out where I keep going wrong. Can someone help me please?

## #2 Re: Help Me ! » Word problem w/ distance formula and rational exponents » 2011-05-03 05:38:28

Thank you so much. Mr. Spock thought that's what it was too. "Live Long and Prosper"

## #3 Help Me ! » Word problem w/ distance formula and rational exponents » 2011-05-02 08:35:12

00jwaj
Replies: 3

Could somebody please help me with this word problem? I can't even figure out what it means in words never mind solve it mathematically Here goes.
In some other universe, Mr. Spock believes he has discovered a relationship between a planets distance D from its sun and the time it takes to orbit its sun.
This formuls is T=√(D^3) where t is in earth years and D=1 corresponds to the distance between the earth and our sun or 93,000,000 miles.
A planet named Freya is 32 times farther from its sun, than earth is from our sun. Estimate the nuimber of earth years required for Freya to orbit its sun according to Mr. Spock's formula written with rational exponents. What is his formula?

Does this make sense to anyone? I sure hope so.
Thanks in advance for any help.