Answer:
Tn = 4(-6)^n-1
Step-by-step explanation:
Write an explicit formula for an, the nth term of the sequence 4, -24, 144, ....
The sequence is a geometric sequence
Tn = ar^n-1
a is the first term
a = 4
r = -24/4 =144/-24
r = -6
Substitute
Tn = 4(-6)^n-1
As we can see on the picture we have a rectangle and half of circle.
The areas for half circle and rectangle are:

The area of the figure is the sum of the area of half circle and rectangle. Also the height of a rectangle (6ft) is a diameter of a half circle therefore the radius of half circle is 6ft ÷ 2 = 3ft.
Now we calculate the areas.

The area of the figure is approximately 74ft squared.
Hope this helps.
r3t40
Z because 63 is larger than 55 and 62
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