Question

Help please

Marcie heated a beaker of water in science class. The scatter plot shows the temperature (y), in degrees Celsius, of the water based on the number of minutes (x) she heated the water.

Part A: The line of best fit for this data is
y = 5.3x + 23. Use this equation to make a conjecture about the temperature of the water in the beaker if heated for 6 minutes.

A.
The water will be about 71⁰C.

B.
The water will be about 55⁰C.

C.
The water will be about 32⁰C.

D.
The water will be about 50⁰C.

Part B: What is the y-intercept in the line of best fit? What does the y-intercept represent in the scatter plot?

A.
5.3; the amount the temperature increases each minute

B.
5.3; the temperature of the water before it is heated

C.
23; the amount the temperature increases each minute

D.
23; the temperature of the water before it is heated

Answer 1

Part A

Given function

• y = 5.3x + 23

The value of y at x = 6:

• y = 5.3*6 + 23 = 54.8° C

The closest choice is :

• B. The water will be about 55⁰C

Part B

The y-intercept is the value of y when x = 0

• y = 5.3*0 + 23 = 23° C

This is the initial temperature at zero minute time, before heating is applied.

Correct choice is:

• D. 23; the temperature of the water before it is heated