164k views
5 votes
Biologists have observed that the chirping rate of crickets of a certain species is related to temperature, and the relationship appears to be nearly linear. A cricket produces 120 chirps per minute at 70 degrees F and 168 chirps per minute at 80 degrees F.

A. Find a linear equation that models the temperature T when crickets are chirping at x chirps per minute.
B. If the crickets are chirping at 150 chirps per minute, estimate the temperature.
C. Find the y-intercept of the line. What does it represent?

User Gene M
by
8.4k points

1 Answer

6 votes

Answer:

A. To find a linear equation that models the temperature T when crickets are chirping at x chirps per minute, we need to use two points that are known. In this case, we are given that a cricket produces 120 chirps per minute at 70 degrees F and 168 chirps per minute at 80 degrees F. We can use these two points to find the slope and y-intercept of the line.

The slope of a line can be found using the formula: m = (y2 - y1) / (x2 - x1)

In this case, we can substitute the given values to get:

m = (168 - 120) / (80 - 70) = 48/10 = 4.8

The y-intercept of a line can be found using the formula: b = y - mx

We can use the point (70, 120) and the slope that we found to get:

b = 120 - (4.8 * 70) = -264

So the linear equation that models the temperature T when crickets are chirping at x chirps per minute is:

T = 4.8x - 264

B. If the crickets are chirping at 150 chirps per minute, we can substitute this value for x in the equation we found above to estimate the temperature:

T = 4.8x - 264

T = 4.8(150) - 264 = 720 - 264 = 456

So the estimated temperature is 456 degrees F.

C. The y-intercept of the line is -264, it represents the temperature when x (chirps per minutes) is zero. In this case it represents the temperature when the cricket is not chirping which is impossible, so it doesn't have any physical meaning.

User Crusaderky
by
8.4k points