The speed of sound in air is a linear function of the air temperature. When the air temperature is 10°C, the speed of sound is 337 m/s. When the air temperature is 30°C, the speed of sound is 349 m/s. Can you please explain the process of writing this function as a linear equation?

The answer is s-337=0.6(t-10), but I don't know how the textbook got this answer.

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  process: substitute the given point values into the 2-point form of the equation for a line

Step-by-step explanation:

There are more than a half-dozen different forms of the equation for a line. They are useful for different purposes. One of them is the "two-point form".

Using x as the independent variable, and y as the dependent variable, the equation can be written as ...

  y -y1 = (y2 -y1)/(x2 -x1)/(x -x1)

where (x1, y1) and (x2, y2) are the two points.

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Here, your two points are ...

  (t, s) = (10, 337) and (30, 349)

Using s in place of y, and t in place of x, these two points go into the formula like this:

  s -337 = (349 -337)/(30 -10)(t -10)

Simplifying the fraction, this is ...

  s -337 = (12/20)(t -10)

And writing it as a decimal, we get ...

  s -337 = 0.6(t -10)

Additional comments

Adding y1 to both sides of the above form gives you ...

  y = (y2 -y1)/(x2 -x1)/(x -x1) +y1

This is the form I usually prefer to use, because it can lead directly to slope-intercept form. For this problem, the form shown above gets you to the answer you're looking for.

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This "two-point form" is an expansion of the "point-slope form", which is ...

  y - k = m(x -h) . . . . . . . line with slope m through point (h, k)

where the equation for slope is ...

  m = (y2 -y1)/(x2 -x1)

and (x1, y1) is used instead of (h, k).

in mathematics, a constraint is a condition of an optimization problem that the solution must satisfy. there are several types of constraints—primarily equality constraints, inequality constraints, and integer constraints. the set of candidate solutions that satisfy all constraints is called the feasible set.

hoped i'm right lol

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