Let’s write an equation to represent this line in the form y=mx+b. Start by finding m, or the slope. What is the slope of this line? In other words, what is the change in degrees for each minute?

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y
(6, 150)(11, 250)
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Time (minutes)
Temperature (°F)
y= mx + b

Slope =

1 answer

To find the slope \( m \) of the line that passes through the two points (6, 150) and (11, 250), we can use the slope formula:

\[ m = \frac{y_2 - y_1}{x_2 - x_1} \]

Using the given points:

  • \( (x_1, y_1) = (6, 150) \)
  • \( (x_2, y_2) = (11, 250) \)

Substituting the values into the slope formula:

\[ m = \frac{250 - 150}{11 - 6} = \frac{100}{5} = 20 \]

Thus, the slope \( m \) is 20. This means the temperature increases by 20 degrees Fahrenheit for each minute.

Now that we have the slope, we can use point-slope form to find the equation of the line in the form \( y = mx + b \). We can use one of the points (let's use (6, 150)) to find \( b \).

Starting with the slope-intercept form:

\[ y = mx + b \]

Substituting \( m \) and one of the points:

\[ 150 = 20(6) + b \]

Calculating the right side:

\[ 150 = 120 + b \]

Solving for \( b \):

\[ b = 150 - 120 = 30 \]

Now we can write the equation of the line:

\[ y = 20x + 30 \]

Final answer:

  • Slope \( m = 20 \)
  • Equation: \( y = 20x + 30 \)