The radius of a circle is greater than the radius of other circle by 3m.The sum of their area is 89 pie m square.Find the radius of each circle.Brainly
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Secondary SchoolMath 5+3 pts
The radius of a circle is greater than the radius of other circle by 3m . The sum of their areas is 89π m^2 . Find the radius of each circle.
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Navneetsharawat03 · Helping Hand
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Josimagic Ambitious
Answer:
radius of smaller circle = 5m
radius of larger circle = 8m
Step-by-step explanation:
Formula:-
Area of circle with radius r is given by,
Area of circle, A = πr²
Let 'r' be the radius of smaller circle, then radius of large circle = r+3
It is given that sum of areas = 89π m^2
To find r
Sum of areas = πr² + π(r +3)² = 89π m^2
⇒ π[r² + (r +3)²] = 89π
⇒ r² + (r +3)² = 89
⇒ r² + r² + 6r + 9 = 89
⇒ 2r² + 6r + 9 - 89 = 0
⇒ 2r² + 6r - 80 = 0
⇒ r² + 3r - 40 = 0 ----(1)
eq(1) is a quadratic equation.
Solving we get
r = 5 and r = -8
we take +ve values, so r = 5
Therefore radius of smaller circle = 5m
And radius of larger circle = r + 3 = 5 = 3 = 8m