ANSWER
2(32-343x)
As calculated in the photo above
Hello from MrBillDoesMath!
Answer:
r^4- 29r^2 + 100
Discussion:
Rearrange the terms in the product as follows:
(r+2)(r-2) * (r-5)(r+5) =
(r^2 - 4) * (r^2-25) =
f^4 - (25+4)r^2 + 4*25 =
r^4- 29r^2 + 100
Thank you,
MrB
Diameter = 10.0002 inches, or 10 inches since were rounding to the nearest whole number.