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
The solution would be: a = 3/4
Answer:
x=7
Step-by-step explanation:
3(x+1)+5(x+1)=64
(3+5)(x+1)=64
8(x+1)=64
8x+8=64
8x=56
x=7
Answer:
any score that lies between 88.8 and 97.2 is within one std. dev. of the mean
Step-by-step explanation:
One std. dev. above the mean would be 93 + 4.2, or 97.2. One std. dev. below the mean would be 93 - 4.2, or 88.8.
So: any score that lies between 88.8 and 97.2 is within one std. dev. of the mean.
Answer:
Option B is correct
Step-by-step explanation:
Given that:
and 
are supplementary.
prove that: 
It is given that:
and are supplementary.
By definition of supplementary
⇒
.....[1]
From the figure, you can see that:
and 
are also supplementary.
⇒
.....[2]
By [1] and [2] we have;
⇒
Simplify:
Since ∠2 and ∠3 are corresponding angles.
Corresponding angles states when the two lines are parallel, then Corresponding Angles are equal and vice versa.
by definition we have;
proved!
