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The speed limit on a road drops down to 15 miles per hour around a curve. Mr. Gerard slows down by 10 miles per hour as he drives around the curve. He never drives above the speed limit. What speed was Mr. Gerard driving before the curve The speed limit on a road drops down to 15 miles per hour around a curve. Mr. Gerard slows down by 10 miles per hour as he drives around the curve. He never drives above the speed limit. What speed was Mr. Gerard driving before the curve? Graph the solution.? Graph the solution.

User Ademers
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1 Answer

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Answer:

Mr. Gerard speed was at most 25 miles per hour before the curve

Explanation:

How to solve the speed Mr. Gerard was driving before the curve

Let’s just assume that Gerard went exactly the speed limit 15 miles per hour (mph) after when he slowed down by 10 miles per hour and drove around the curve. The reason why I’m using exactly 15mph is because it’s the max speed he can go. He can go 15 miles per hour and still be safe, but it’s just that he can’t go any faster than that.

Now, you can do 15 + 10 to find the speed he went before he drove around the curve. So, that would be 25mph before he drove around the curve.

You might be asking: What if he went slower than 25mph before he drove around the curve, and what if he went faster than 25mph?

-When he drives exactly 25mph and slows down by 10mph when he makes the turn around the curve, he’s going exactly 15mph which it safe for him because it’s not faster than 15mph.

-It could be possible that he went slower than 25mph before he drove around the curve, but he still will be safe because when he makes the turn around the curve and slows down by 10 miles per hour, now he’ll reach below 15 miles per hour which is even safer for him. Here’s an example for you to understand: Let’s say he drove 23mph before the curve (which is less than 25mph). As soon as he makes the turn around the curve, he slows down by 10mph. So after he goes around the curve, he’s going 13mph, which is less than the speed limit 15mph. You can take any number less than 25mph and he’ll still be safe because it will be less than 15mph.

-Now, if he went faster than 25mph, he wouldn’t be safe anymore because after when he slows down by 10mph and goes around the curve, he’ll be above the speed limit of 15mph. Here’s an example for you to understand: Let’s say he drove 27mph before the curve (which is faster than 25mph). As soon as he makes the turn around the curve, he slows down by 10mph. So after he goes around the curve, he’s going 17mph, which is faster than the speed limit 15mph.

Answer: Mr. Gerard speed was at most 25 miles per hour before the curve

Graphing it

A way to graph this is to write out a compound inequality. You can write it as:

0 < y ≤ 25 ⇒ Where any speed has to be less than or equal to 25 miles per hour, because 25 miles per hour is the most/biggest speed Mr. Gerard can drive. But it has to be greater than 0 because you can’t go negative miles per hour, or 0 miles per hour

The graph is shown below ↓

I don’t know what graph you want, or how your teacher wants you to graph it. So I put two options for you :)

I hope you understand and that this helps with your question! :)

The speed limit on a road drops down to 15 miles per hour around a curve. Mr. Gerard-example-1
The speed limit on a road drops down to 15 miles per hour around a curve. Mr. Gerard-example-2
User Neall
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