The area would be 25π inches.
Since the cross-section goes through the center of the sphere it will be a circle. The area of a circle is given by A = πr²; for our circle, since the diameter is 10 inches, the radius is 5;
A = π(5²) = 25π
Answer: 
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Work Shown:

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Explanation:
The idea is to first get all the y terms to one side. I did this by subtracting 2y from both sides in the third step.
Then factor out y and divide both sides by (8x-2)
Afterward there's the optional steps of simplifying (as shown in the final two steps).
Answer:
155 sheets
Step-by-step explanation:
Warner used 75 of the printer paper .
He now has 80 sheets left .
Sheets in the package when warner bought it = used + remaining sheets
That’s 75 + 80
= 155
The package had 155 sheets when warner bought it .
I don’t know:( But wish I could help. You can come check out some of my questions too!