To graph the equation \( y = -300x + 1200 \), we can start by identifying key components such as the y-intercept and the slope.
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Y-Intercept: This occurs when \( x = 0 \): \[ y = -300(0) + 1200 = 1200 \] So, the y-intercept is \( (0, 1200) \). This means the helicopter starts at a height of 1200 feet.
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Slope: The slope of the equation is -300. This indicates that for every minute (1 unit increase in \( x \)), the height \( y \) decreases by 300 feet.
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Determine another point: To find another point, we can select a value for \( x \). Let's use \( x = 4 \): \[ y = -300(4) + 1200 = -1200 + 1200 = 0 \] So, when \( x = 4 \), the height \( y = 0 \) feet, which indicates that the helicopter reaches the ground after 4 minutes.
Points for the graph:
- Point 1: \( (0, 1200) \) - Starting point at 1200 feet.
- Point 2: \( (4, 0) \) - Ground level after 4 minutes.
Plotting the points:
- Start by plotting the point \( (0, 1200) \) on the y-axis.
- Next, plot the point \( (4, 0) \) on the x-axis.
Drawing the line:
Connect these two points with a straight line, which will slope downwards to the right, reflecting the negative slope of the equation.
Summary of the graph:
- The line starts at \( (0, 1200) \) and goes down to \( (4, 0) \).
- The entire line represents the descent of the helicopter, showing that as time increases, the height decreases linearly until it reaches the ground.
You can use graphing software or graph paper to create a more accurate visualization, using the slope and points identified above to help with the graphing.