(2j+7)(2j−7)
=(2j+7)(2j+−7)
=(2j)(2j)+(2j)(−7)+(7)(2j)+(7)(−7)
=4j2−14j+14j−49
=4j2−49
Answer:
The radius, r₂, of the ball that uses one-half the amount of rubber coating used to cover the 16-inch ball is approximately 4.66 inches
Step-by-step explanation:
The dimension of the ball with known radius = 16-inch
The surface area of the ball with 16-inch radius = 4×π×r² = π·D² = π×16² = 804.24772 in.²
Given that the ball uses one-half the rubber material coating used to cover the 16-inch ball, we have the surface area of the ball = 804.24772 in.²/2 = 402.12386 in.²
The radius, r₂ of the new ball is found as follows;
402.12386 in.² = 4×π×r₂²
r₂² = 402.12386 in.² /(4×π) ≈ 32
r₂ = √32 = 4·√2 ≈ 4.66 inches
The radius, r₂, of the ball that uses one-half the amount of rubber coating used to cover the 16-inch ball ≈ 4.66 inches.
Answer:Take the alternating sum of the digits in the number, read from left to right. If that is divisible by 11, so is the original number. So, for instance, 2728 has alternating sum of digits 2 – 7 + 2 – 8 = -11. Since -11 is divisible by 11, so is 2728.
Hope this helped
I'm guessing you find the length of the hypotenuse using the pythagorean theorem.
a² + b² = c² a and b are the legs and c is the hypotenuse
15² + 8² = c²
225 + 64 = c²
289 = c²
√289 = √c²
17 = c
hope that helps, God bless!
