Answer:
√446 ≈ 21.12 cm
Step-by-step explanation:
The longest dimension of a rectangular prism is the length of the space diagonal from one corner to the opposite corner through the center of the prism. The Pythagorean theorm tells you the square of its length is the sum of the squares of the dimensions of the prism:
d² = (15 cm)² +(11 cm)² +(10 cm)² = (225 +121 +100) cm² = 446 cm²
d = √446 cm ≈ 21.12 cm
The longest line segment that can be drawn in a right rectangular prism is about 21.12 cm.
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<em>Additional comment</em>
The square of the face diagonal is the sum of the squares of the dimensions of that face. The square of the space diagonal will be the sum of that square and the square of the remaining prism dimenaion, hence the sum of squares of all three prism dimensions.
Answer:
see down
Step-by-step explanation:

Upwards from 1 to 2 is your Answer (see attachments)
Quadratic in equality is quadratic function that is compared to another function like: x^2+4x-1<2x-3. the answer for x must comply to both sides.
For get the solution of this task, we must make the system of equations.First it: "The quotient between the sum of two numbers and one of them is equal to 3" Let's take two values: a and b.(a+b)/b=3 --- it's will be first equation in our system.
and "The inverse of double the sum of them and equal to 1/6"1/2(a+b)=1/6 it's will be second equation in our system.
Attention at parenthesis.
System(a+b)/b=31/2(a+b)=1/6
by the first equation:(a+b)/b=3a+b=3ba=2b --- we will use this equation for second equation in system
1/2(2b+b)=1/61/3b)=1/63b=6b=2 and a=2b, that's mean a=1.The answer is pair (1;2)