Answer:
The difference of two cubes is equal to the difference of their cube roots times a trinomial, which contains the squares of the cube roots and the opposite of the product of the cube roots. A number's opposite is that same number with a different sign in front.
Step-by-step explanation:
Let

be the amount of time it takes to perform an arm routine and

be the amount of time it takes to perform an abdominal routine. We see:


Subtracting the second equation from the first gives

. Substituting gives

, so

and

.
Thus, an arm routine takes ten minutes and an abdominal routine takes thirty minutes.
Of 3.............................................
<h3>
Answers</h3><h3>diameter = 14</h3><h3>radius = 7</h3><h3>area = 154</h3>
these are all approximate
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Explanation:
C = pi*d is the formula for the circumference. We know that C = 44 approximately, so,
C = pi*d
d = C/pi
d = 44/3.14
d = 14.01 approximately
d = 14 also approximate
take half of this to get the radius
r = d/2 = 14/2 = 7
Then use this radius to find the circle's area
A = pi*r^2
A = 3.14*7^2
A = 153.86
A = 154 rounding to the nearest whole number