Answer:
Four (4) pounds
Step-by-step explanation:
Because we required two (2) pounds to stretch the spring eight (8) inches, we need double the force to stretch it sixteen (16) inches. Sixteen is just double the original amount, meaning we need four (4) pounds to stretch the spring sixteen inches.
Hope this helps!
Step-by-step explanation:
We have

First, 125 is a perfect cube because

and
x^3 is a perfect cube because

so we can use the difference of cubes identity

Let say we have two perfect cubes:
64 because 8×8×8=64
and 27 because 3×3×3=27 and let subtract

we know that

but using the difference of cubes identity we should get the same thing.
Remeber cube root of 64 is 4 and cube root of 27 is 3 so we have


So the difference of cubes works for real numbers. This is a good way to help remeber the identity using real numbers.
Back on to the topic,
we know that 5 is cube root of 125 and x is the cube root of x^3 so we have


I think its multiplying im gonna say 144
|4r + 8| ≥ 32
Split this expression into two expressions:
First ⇒ 4r + 8 ≥ 32 and second ⇒ 4r + 8 ≤ - 32
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First expression: 4r + 8 ≥ 32
Subtract 8 from both sides.
4r ≥ 24
Divide both sides by 4.
r ≥ 6
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Second expression: 4r + 8 ≤ - 32
Subtract 8 from both sides.
4r ≤ -40
Divide both sides by 4.
r ≤ -10
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Your answer is 