Question

Entomologists are biological scientists who study insects. Entomologists studying tree crickets have found that they chirp at different rates depending on the temperature.

The number of chirps per minute, C, that the tree cricket makes is linearly dependent on the temperature, T, in Fahrenheit. The crickets do not chirp at all below 35 degrees and at 65 degrees they chirp about 138 times per minute.

A) Express the number of chirps, C, as a function of the temperature, T. Be sure to use function notation:____________

B) How many chirps per minute will crickets make at 80 degrees?

Answer 1

@satellite73

Answer 2

find the equation of the line between the two points \((0,-35)\) and\((65,138)\)
find the slope first,
then the y intercept is given to you by the first point, so you don't need to find it

Answer 3

so the y intercept is gonna be -35 after i find the slope?

Answer 4

yes it is

Answer 5

so y=173/65x-35

Answer 6

it is going to be \[C=mT-35\] as soon as you find \(m\)

Answer 7

c=173/65t-35

Answer 8

hold on

Answer 9

what about part two?
B) How many chirps per minute will crickets make at 80 degrees?

Answer 10

i may have made a mistake here

Answer 11

oops yes i did

Answer 12

the first is the temp, not the second
the two points are \((-35,0)\) and \((65,138)\)

Answer 13

so c=23/5t-35

Answer 14

no the y intercept is not \(-35\) i screwed up

Answer 15

what did you get for the slope/

Answer 16

0
sorry

Answer 17

23/5

Answer 18

138/100=69/50

Answer 19

yeah that

Answer 20

c=69/50t-0

Answer 21

what about part 2
B) How many chirps per minute will crickets make at 80 degrees?

Answer 22

no you just got the slope you don't have the equation for the line yet
you need the point slope formula

Answer 23

okay

Answer 24

\[C-0=\frac{69}{50}(x+35)\]

Answer 25

i would use decimals \[C=1.38(T+35)\]

Answer 26

c=69/50x+483/10

Answer 27

it has to be fractions :/

Answer 28

ok then what you got is right

Answer 29

okayy
what about B

Answer 30

could you help with that?

Answer 31

where you see a T, put 80

Answer 32

ok

Answer 33

i would still use decimals, but whatever

Answer 34

so 552/5

Answer 35

its an online probram, it has to be fraction. it sucks

Answer 36

i get this
http://www.wolframalpha.com/input/?i=69*80%2F50%2B483%2F10

Answer 37

WHAT im so lost

Answer 38

let me try it

Answer 39

its wrong

Answer 40

here is the line
http://www.wolframalpha.com/input/?i=line+(-35,0),+(65,138)

Answer 41

and here it is for T = 80
http://www.wolframalpha.com/input/?i=483%2F10%2B(69+x)%2F50+for+x%3D80

Answer 42

did you use function notation?

Answer 43

what do you mean?

Answer 44

\[C(T)=...\]

Answer 45

yes :/

Answer 46

thank you tho

Answer 47

sorry
not sure why it says you are wrong...