Answer:
Step-by-step explanation:
That's B: the surface area.
The volume of the sphere is V = (4/3)πr³; A = 4πr² happens to be the derivative of V with respect to r.
Answer:
21
Step-by-step explanation:
![\left[\begin{array}{cc}5&9\\-6&9\end{array}\right] +6\left[\begin{array}{cc}-5&2\\7&8\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D5%269%5C%5C-6%269%5Cend%7Barray%7D%5Cright%5D%20%2B6%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D-5%262%5C%5C7%268%5Cend%7Barray%7D%5Cright%5D)
Multiply the second matrix by 6.
![\left[\begin{array}{cc}5&9\\-6&9\end{array}\right] +\left[\begin{array}{cc}-30&12\\42&48\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D5%269%5C%5C-6%269%5Cend%7Barray%7D%5Cright%5D%20%2B%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D-30%2612%5C%5C42%2648%5Cend%7Barray%7D%5Cright%5D)
Add the corresponding cells in each matrix.
![\left[\begin{array}{cc}5-30&9+12\\-6+42&9+48\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D5-30%269%2B12%5C%5C-6%2B42%269%2B48%5Cend%7Barray%7D%5Cright%5D)
![\left[\begin{array}{cc}-25&21\\36&57\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D-25%2621%5C%5C36%2657%5Cend%7Barray%7D%5Cright%5D)
Answer:
Step-by-step explanation:
679
Answer:
33
Step-by-step explanation:
If m = Mother's age and d = daughter's age, we can make the following equations
m = 3d
m + d = 44
Now, using substitution, we can substitute m for 3d in the second equation:
3d + d = 44, 4d = 44, d = 11
Then, we can plug d into the first equation: m = 3(11) = 33
<h3>
Answer: $628 </h3>
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Work Shown:
x = Ali's share
4x = Pip's share, because it is four times bigger due to the ratio 4:1
x+4x = 5x = total amount of money = 785
5x = 785
x = 785/5
x = 157 dollars is Ali's share
4x = 4*157 = 628 dollars is Pip's share
Note that 157+628 = 785 to help confirm the answer.