Answer:
C
Step-by-step explanation:
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:
10π cm
Step-by-step explanation:
Given
Area of the circle=25π cm^2
Solution
πr^2=25π
r^2=25
r=√25
r=5
So circumference of the circle=2πr
=2π×5
=10π cm
So the answer is 10π cm
Answer: 7892
explanation: add each number individually left to right. 4+3 , 2+6 , 9+0 , 0+2
Answer:
Step-by-step explanation:
a) the equation representing the parabola is expressed as
h = -16t² - 4t + 20
c) to determine the height after 25 seconds, we would substitute 25 for t into the given equation. It becomes
h = -16(25)² - 4(25) + 20
h = - 10000 - 100 + 20
h = - 10080
d) when the coin lands on the ground, the height would be 0. Therefore,
-16t² - 4t + 20 = 0
Dividing both sides of the equation by 4, it becomes
- 4t² - t + 5 = 0
- 4t² - 5t + 4t + 5 = 0
- t(4t + 5) + 1(4t + 5) = 0
- t + 1 = 0 or 4t + 5 = 0
t = 1 or t = - 5/4
Since t cannot be negative, then t = 1 second