Answer:
54 keys
Step-by-step explanation:
If there are 6 keys on each of the nine key rings, you times 6 by 9 to get 54.
10x^2 = 50x.....subtract 50x from both sides
10x^2 - 50x = 0...factor
10x(x - 5) = 0
10x = 0
x = 0 <== this one is eliminated because x cannot be zero
x - 5 = 0
x = 5 <== ur answer
A = pi * r^2
<span>A = 3.14 * 50^2 </span>
<span>A = 7,850 square miles (area of the 50 mile broadcast signal)
A = pi * r^2
A = 3.14 * 75^2
A = </span>17,662.5 = 17,663 square miles (area of the 75 mile relayed signal)
Now we just need to subtract the 50 mile signal from the 75 mile signal, so:
17,663 - 7,850 = <span>9,813 square miles greater
Hope this helps :)
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