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Answer: Choice D</h3>
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Explanation:
The inequality sign has an "or equal to", which means the boundary line will be solid. We can rule out choices B and C because they have dashed boundary lines.
A solid boundary line means that points on the boundary are part of the solution set.
Now let's see what happens when we plug in a point like (x,y) = (4,0). This will tell us how to shade the blue region.
This is false because -20 is not larger than -1. It's the other way around.
This tells us the point (4,0) is not in the blue shaded region, and it's not on the boundary line either. We can rule out choice A because of this.
The only thing left is choice D, which is the final answer. I recommend plugging a point from this region into the inequality to confirm we have a true statement.
For this case, the first thing we must do is define variables.
We have then:
x: altitude of the plane in feet
y: final temperature
The equation modeling the problem for this case is given by:
Thus, evaluating the function for x = 11,000 ft. Height we have:
Answer:
the temperature at an altitude of 11,000 ft is 47.6 F