Question

The table gives the boiling point of water at different altitudes.

Altitude (1,000 feet)Boiling Point of Water (°F)
0 212.0
0.5 211.1
1.0 210.2
2.0 208.4
2.5 207.5
3.0 206.6
4.0 204.8
4.5 203.9
Based on the table, the linear equation that represents the change in water’s boiling point for every 1,000-foot change in altitude has a slope of ____ units.

Answer 1

1.8

Explanation:

Altitude (1,000 feet) Boiling Point of Water (°F)

0 212.0

0.5 211.1

1.0 210.2

2.0 208.4

2.5 207.5

3.0 206.6

4.0 204.8

4.5 203.9

Formula of slope m =
`(y_2-y_1)/(x_2-x_1)`

`(x_1,y_1)=(0,212)`

`(x_2,y_2)=(0.5,211.1)`

Substituting the values in the formula

`m=(211.1-212)/(0.5-0)`

`m=(-0.9)/(0.5)`

`m= -1.8`

Hence the linear equation that represents the change in water’s boiling point for every 1,000-foot change in altitude has a slope of 1.8 units.

Answer 2

We will use the points (2 , 208.4) and (1 , 210.2) to find the slope of the line.

m = (210.2 - 208.4) / (1 - 2)
m = -1.8

The boiling point of water decreases by 1.8 °F for every 1000-foot increase in altitude.