the surface area of a sphere is a=4 pie r squared where r is the radius of the sphere. waht is the radius, rounded to the nearest tenth, of a ball with surface area equal to 85 square inches? below the question is A. 2.6 in. B 6.8 in. C. 2.7 in. D 6.7 in.
85=4(pi)(r^2). Divide each side by 4 to get 21.25=(pi)(r^2). Then divide pi from both sides, so you get (r^2)=6.76... Take the square root of each side so the radius=2.6 inches.
To find the radius of the ball with a surface area of 85 square inches, you can use the formula A = 4πr^2, where A is the surface area and r is the radius.
Given: A = 85 square inches
You can re-arrange the formula to solve for r:
A = 4πr^2
Divide both sides of the equation by 4π:
A / (4π) = r^2
Substitute the given value of A:
85 / (4π) = r^2
Now, you can solve for r by taking the square root of each side to get the radius:
√(85 / (4π)) = r
Approximating the value of π as 3.14 and evaluating the expression:
r ≈ √(85 / (4 * 3.14))
r ≈ √(21.5 / 3.14)
r ≈ √6.8547
r ≈ 2.62
Rounded to the nearest tenth, the radius of the ball is approximately 2.6 inches.
Therefore, the correct answer is A. 2.6 in.