Part (a)
The picture alone, without the frame, is 16 by 20
When accounting for the frame, the larger rectangle is 16+2x by 20+2x
We add up all four sides to get the perimeter
(16+2x)+(20+2x)+(16+2x)+(20+2x)
8x+72
or you can use this perimeter of a rectangle formula
P = 2(L+W)
P = 2(20+2x+16+2x)
P = 2(4x+36)
P = 8x+72
Answer: 8x+72
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Part (b)
Multiply the length and width to find the area of the rectangle.
area = length*width
A = L*W
A = (20+2x)*(16+2x)
A = 20(16+2x) + 2x(16+2x)
A = 320+40x + 32x + 4x^2
A = 4x^2 + 72x + 320
Answer: 4x^2 + 72x + 320
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Part (c)
Plug x = 2 into the perimeter equation found in part (a)
P = 8x+72
P = 8*2+72
P = 16+72
P = 88
Now plug x = 2 into the area equation found in part (b)
A = 4x^2 + 72x + 320
A = 4(2)^2 + 72(2) + 320
A = 4(4) + 72(2) + 320
A = 16 + 144 + 320
A = 160+320
A = 480
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Answers:
Perimeter = 88 inches
Area = 480 square inches
Given: "<span>B(t)=4*e^0.8t, How many hours will it take for the population to grow to 400?" Set B(t) = 400. Then:
400=4*e^(0.8t), or
100 = e^(0.8t)
Take the natural log of both sides, obtaining
ln 100
ln 100 = 0.8t. Then t = ----------- = 5.76 hours.
0.8</span>
Answer:
3/8
Step-by-step explanation:
1/4= 2/8
5/8-2/8=3/8
Answer:
-9x² + 25
Step-by-step explanation:
To solve, use FOIL. FOIL:
First
Outside
Inside
Last
Solve "First":
(3x)(-3x) = -9x²
Solve "Outside":
(3x)(-5) = -15x
Solve "Inside":
(-5)(-3x) = +15x
Solve "Last":
(-5)(-5) = +25
Combine like terms:
-9x² - 15x + 15x + 25
-9x² (-15x + 15x) + 25
-9x² + 25
-9x² + 25 is your answer.
~
12 ft shadow / 4 ft shadow = 3
16.5 ft / 3 = 5.5 ft
The zookeeper is 5.5 feet tall