The relationship between altitude and the boiling point of a liquid is linear. At an altitude of 8500 ft, the liquid boils at 199.55 F. At an altitude of 4300 ft, the liquid boils at 206.69 F. Write an equation giving the boiling point b of the liquid, in degrees Fahrenheit, in terms of altitude a, in feet. What is the boiling point of the liquid at ft?

b = -0.0013a + 211

Step-by-step explanation:

Since the relationship is linear, we can use a linear equation. The formula in slope-intercept form is .

As the question specifies to use a for altitude and b for boiling point, change the variables equation to

b is the boiling point.

m is the slope.

a is the altitude.

c is the y-intercept.

To find the slope, we can use the equation  except x is a and y is b.

The sets of information given are:

8500 ft, the liquid boils at 199.95°  (This can be info set 1)

4300 ft, the liquid boils at 205.41°  (This can be info set 2)

Substitute the info sets into the equation. The subscripts mean which info set to get the numbers from.

m = -0.0013

Find the y-intercept by substituting m = -0.0013 and a random info set. I will use info set 1. Isolate c, the only variable.

b = ma + c

199.95 = (-0.0013)(8500) + c  <= Simplify

199.95 = -11.05 + c

199.95 + 11.05 = -11.05 + 11.05 + c  <=add 11.05 on both sides to isolate c

c = 211  <= y-intercept

Put the y-intercept and slope into the equation of a line:

b = ma + c

b = -0.0013a + 211 <= This is the equation for the problem.

in mathematics, a function is a relationship between two variables such that the value of one of the variables, called the dependent variable, is determined by the value of the other variable, called the independent variable. there is a specific term we use to describe the set of independent variables of a function.