Houghton Mifflin Harcourt Algebra 1, 2015
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Houghton Mifflin Harcourt Algebra 1, 2015 View details
2. Point-Slope Form
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Exercise 17 Page 210

Write the equation in point-slope form for this situation and use it find the actual altitude of the balloon after 4 minutes of ascending.

No.

Practice makes perfect

Let's start with writing the equation in point-slope form and then use it to determine whether the statement is true.

Write the Equation

In order to write the equation in point-slope form, we need to know the slope and a point that solves the equation. We are told that the hot air balloon ascends at a steady rate of 120 feet per minute. Since slope represents a constant rate of change, we can conclude that m= 120. Let's put this into our equation. y-y_1= 120(x-x_1)We are also given that, after 3 minutes of ascending, the balloon is at an altitude of 2330 feet. Let x represent the number of minutes and y represent the number of feet. Substituting 3 for x and 2330 for y, we get the final equation. y- 2330=120(x- 3)

Check the Statement

To determine whether the balloon will reach an altitude of 2500 feet in 4 minutes, we can substitute x with 4 and calculate the actual altitude after 4 minutes of ascending. Then we will compare the result with 2500 and see if the statement is true.

y-2330=120(x-3)
y-2330=120( 4-3)
y-2330=120( 1)
y-2330=120
y=2450

The balloon will be at an altitude of 2450 feet, which is less than 2500. Therefore, it will not reach an altitude of 2500 feet in 4 minutes.