Question

How to figure out the temperature of a lake using x for the feet or the Depth and for the degrees Celsius use (3900x+1000)/(3x^2+100) with the answer of the degrees celsius being 8.44 looking like

8.44=(3900x+1000)/(3x^2+100)
i need the depth

Answer 1

Cross multiply to get:
8.44(3x²+100)=3900x+1000
Rearrange:
25.32x²-3900x-156=0
Solve for x using quadratic formula:
x=-0.03999 or x=154.07 approx.

Answer 2

thank you ill try that

Answer 3

it worked i have been working for two days on that problem thank you so much

Answer 4

You're welcome!

Answer 5

I have another one instead of using the 8.44 I have to do the same question but now I have to put it with 6.74 like this

6.74=(3900x+1000)/(3x^2+100)

This very fustratimg I have been in school in so long after all I am 60yr old

Answer 6

I have another one instead of using the 8.44 I have to do the same question but now I have to put it with 6.74 like this

6.74=(3900x+1000)/(3x^2+100)

i have figure out that
a=-20.22
b= 3900
c= 326

On the quadritic formula table

-3900+Square root ()/-40.44

Answer 7

Answered to your other post.