A ratio can be written in three different ways: 3 to 4, 3:4, and 3/4
What does this mean? It means that for every group of 7 students (3+4) there are 3 boys and 4 girls. And how many groups do we have? We have:
245/7= 35 We have 35 groups, and we just said that each group has 3 boys and 4 girls:
35*3= 105 boys
35*4= 140 girls
_ _ _---------
The critical points of <em>h(x,y)</em> occur wherever its partial derivatives
and
vanish simultaneously. We have

Substitute <em>y</em> in the second equation and solve for <em>x</em>, then for <em>y</em> :

This is to say there are two critical points,

To classify these critical points, we carry out the second partial derivative test. <em>h(x,y)</em> has Hessian

whose determinant is
. Now,
• if the Hessian determinant is negative at a given critical point, then you have a saddle point
• if both the determinant and
are positive at the point, then it's a local minimum
• if the determinant is positive and
is negative, then it's a local maximum
• otherwise the test fails
We have

while

So, we end up with

A fluid ounce is a customary unit for measuring liquid capacity.
Q4, 4y²=60
y=√15 ( i am not sure)
q6, (5+y) ²=81
5+y=9
y=4
q7 (x+4) (x) =77
x²+4x-77=0
(x+11) (x-7) =0
x=-11(rej) or x=7
therefore ,length= 7+4=11cm
breadth=7cm
Answer:
![\left[\begin{array}{ccc}4&19&-5\\7&0&-14\end{array}\right] + \left[\begin{array}{ccc}-8&7&0\\-1&17&6\end{array}\right] = \left[\begin{array}{ccc}-4&26&-5\\6&17&-8\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D4%2619%26-5%5C%5C7%260%26-14%5Cend%7Barray%7D%5Cright%5D%20%2B%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-8%267%260%5C%5C-1%2617%266%5Cend%7Barray%7D%5Cright%5D%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-4%2626%26-5%5C%5C6%2617%26-8%5Cend%7Barray%7D%5Cright%5D)
Step-by-step explanation:
To add two matrices you just need to add the corresponding entries together. In this case, we have that:
![\left[\begin{array}{ccc}4&19&-5\\7&0&-14\end{array}\right] + \left[\begin{array}{ccc}-8&7&0\\-1&17&6\end{array}\right]=\left[\begin{array}{ccc}4-8&19+7&-5 + 0\\7-1&0+17&-14+6\end{array}\right] = \left[\begin{array}{ccc}-4&26&-5\\6&17&-8\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D4%2619%26-5%5C%5C7%260%26-14%5Cend%7Barray%7D%5Cright%5D%20%2B%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-8%267%260%5C%5C-1%2617%266%5Cend%7Barray%7D%5Cright%5D%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D4-8%2619%2B7%26-5%20%2B%200%5C%5C7-1%260%2B17%26-14%2B6%5Cend%7Barray%7D%5Cright%5D%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-4%2626%26-5%5C%5C6%2617%26-8%5Cend%7Barray%7D%5Cright%5D)
Then, we conclude that the sume of the two matrices is:
![\left[\begin{array}{ccc}4&19&-5\\7&0&-14\end{array}\right] + \left[\begin{array}{ccc}-8&7&0\\-1&17&6\end{array}\right] = \left[\begin{array}{ccc}-4&26&-5\\6&17&-8\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D4%2619%26-5%5C%5C7%260%26-14%5Cend%7Barray%7D%5Cright%5D%20%2B%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-8%267%260%5C%5C-1%2617%266%5Cend%7Barray%7D%5Cright%5D%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-4%2626%26-5%5C%5C6%2617%26-8%5Cend%7Barray%7D%5Cright%5D)