In a cancer research lab, you are observing the growth of cancer cells in two specimens, A & B. Specimen A presently has 2160 cells and specimen B has 1200 cells. After recording data for several days, you later determine that the number of cells in specimen A, N(A), is growing ny the formula:

N(A) = 24t^2 + 588t + 2160

where t is the number of days the specimen is in the test environment. Likewise, the data for specimen B indicates that its number of cells, N(B), is

N(B) = 36t^2 + 780t + 1200

a. Write a rational expression and simplify the ratio of N(A) to N(B). Show any intermediate steps.

b. On which day did the number of cancer cells in specimen B overtake that of specimen A?

c. How many cancer cells had developed in specimen B as of the day you calculated in (b)? Show your calculation and write this number using scientific notation.

Solution Summary

A rational expression wordproblem is solved. The solution is detailed and well presented. The response received a rating of "5/5" from the student who originally posted the question.

Look at the example application of rationalexpressions on page 315 of your textbook. Then, using the Internet, locate a Web site that has an additional example that interests you. (Use the search words "rationalexpressionsapplications.") Following the example of problems 51-54 on page 315, formulate two to three values for yo

How is doing operations (adding, subtracting, multiplying, and dividing) with rationalexpressions similar to or different from doing operations with fractions? Can understanding how to work with one kind of problem help in understanding how to work another type? When might you use this skill in real life?

#1) Subtract these two rationalexpressions:
2/(3x-1) - 1/(x+1)
#2) Solve for x (find the values of x) in the following equation:
2/(3x-1) - 1/(x+1) = 0
Hint: Use the answer of problem #1 (simplified expression).

I'm having a difficult time figuring out some of these! For some reason the -1 in this problem is throwing me off - I think! Here's what I came up with last time, I keep getting a different answer each time I work it.
3/(y+5) -1 = (4-y)/(2y+10)
3/(y+5)-1 = (4-y)/2(y+5)
y is not equal to -5
LCD is 2(y+5)
2(y+5)*3/(y+5) =

When is it necessary to find the least common denominator (LCD) of two rationalexpressions? Describe, in your own words, the process for finding the LCD of two rationalexpressions. How is factoring related to this process? Give an example.
use the following.
4x-5/x-4+1-3x/4-x

What is a rational exponent? How are rational exponents related to radicals? Give an example of how an expression with a rational exponent can be rewritten as a radical, using the following as an example:
(-25)^13

Please help with the following rationalexpressions and to simplify.
Find each function value
2) f(y) = y - 2 / -5 + y; f(-5), f(0), f(10)
6) g(x) 4 -3x / 2
10) f(x) = -4x/-2 + x
14) h(x) = 5 -3x / 2x^2 - 14x + 20
18) Explain how to simplify a rational expression or to write in it lowest terms?
Simplify each rat