The sum exterior angles of a square are:
4*90=360°
The formula for calculating the area of a circle is expressed as;
A = πr²
- Area of the pond = πr²
- Area of the path = Area of the path + pond - area of pond
- Area of path = π(r+1.5)² - πr²
Since the area of the path is equal to the area of the pond, hence;
π(r+1.5)² - πr² = πr²
Add πr² to both sides
π(r+1.5)² - πr² + πr² = πr² + πr²
π(r+1.5)² = 2πr²
(r+1.5)² = 2r²
Expand the parenthesis
r²+3r + 2.25 = 2r²
r²+3r + 2.25 - 2r² = 0
-r² + 3r + 2.25 = 0
r² - 3r - 2.25 = 0
Multiply through by 2
2r² - 6.0r - 4.5 = 0
<em>This proves the required equation</em>
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Learn more on area of composite figures here: brainly.com/question/15981553
Answer: wym
Step-by-step explanation:
Answer:
A) 3 in
General Formulas and Concepts:
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
Equality Properties
<u>Geometry</u>
- Surface Area of a Sphere: SA = 4πr²
- Diameter: d = 2r
Step-by-step explanation:
<u>Step 1: Define</u>
SA = 23 in²
<u>Step 2: Find </u><em><u>r</u></em>
- Substitute [SAS]: 23 in² = 4πr²
- Isolate <em>r </em>term: 23 in²/(4π) = r²
- Isolate <em>r</em>: √[23 in²/(4π)] = r
- Rewrite: r = √[23 in²/(4π)]
- Evaluate: r = 1.35288 in
<u>Step 3: Find </u><em><u>d</u></em>
- Substitute [D]: d = 2(1.35288 in)
- Multiply: d = 2.70576 in
- Round: d ≈ 3 in
1800 because the 18 cant fit in the tens