To solve quadratics, the most correct and effective way, in my opinion, is the quadratic formula:

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Plugging it in, we get:
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So the final answer is:

and
<span>I got 18 x 18 = 324.</span>
Answer:

Step-by-step explanation:
Please consider the complete question.
Sebastian swan laps every day in the community swimming pool. He swam 45 minutes each day, 5 days each week, for 12 weeks. In that time, he swam 1800 laps. What was his average rate in laps per hour?
Let us convert time taken into hours as:


1 hour = 60 minutes. To convert minutes into hours, we will divide total minutes by 60.

Now, we will divide 1800 by 45 to find average rate in laps per hour as:


Therefore, Sebastian's average rate is 40 laps per hour.
This intersection means that u have to find the same number in both sets
the answer is 3 , 7 , 13
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