Any sound from one focus of an ellipse reflects off the ellipse directly back to the other focus. This property explains whispering galleries such as Statuary Hall in Washington, D.C. The whispering gallery shown in the illustration below has the shape of a semi-ellipse. Find the distance sound travels as it leaves focus F and returns to focus F'.
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Please enter your answer as a number without the units, rounded to the nearest tenth.
Fill in the blank(s) with the appropriate word(s).
29.7
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Find the relative extrema of the function and classify each as a maximum or minimum.f(x) = x3 - 12x - 3
A. Relative maximum: (5, 62); relative minimum: (2, -19) B. Relative minimum: (-2, 13); relative maximum: (2, -19) C. Relative maximum: (5, 62); relative minimum: (-3, 6) D. Relative maximum: (-2, 13); relative minimum: (2, -19)
Find the GCF.36, 84, and 72
A. 4 B. 12 C. 3 D. 84
Write the system in the form 
Then solve the linear system by computing 
with a calculator. Round numbers to the nearest tenth, as necessary.2.6x - 0.7y + 5.3z - 3.4w = 12.9 6.5y + 0.7w = -1.8 4.0z - 2.2w = 1.54.9x + 0.6w = 3.2
A. (2.2, 1.1, -6.4, -12.4) B. (-2.2, 1.1, -6.4, 23.3) C. (2.2, 1.1, 7.2, 12.4) D. (2.2, -1.1, -6.4, 7.6)
Solve the problem.A 100-liter mixture of chlorine and water is 8% chlorine. (i) Write a rational expression in x whose values give the percentage (in decimal form) of the mixture that is chlorine when x gallons of water are added to the mixture. (ii) Find the percentage of chlorine in the mixture if 70 gallons of water are added to it. Round to the nearest percent, if necessary.
A. (i) 
;
(ii) 11%
B. (i) 
;
(ii) 154%
C. (i) 
;
(ii) 5%
D. (i) 
;
(ii) 8%