Answer:
An identity matrix, is a matrix that have '1' in the main diagonal. All of the other terms are '0'. When you multiply any matrix by the identity matrix, the result is the same matrix that you multiplied.
Example:
![\left[\begin{array}{ccc}1&0&0\\0&1&0\\0&0&1\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D1%260%260%5C%5C0%261%260%5C%5C0%260%261%5Cend%7Barray%7D%5Cright%5D)
In the set of the real number is the same that the application of identity property.
Every number multiplied by 1 es the same number.
Step-by-step explanation:
Banalties for the second question i think!
Answer:

Step-by-step explanation:
Given


Required
Determine the number of bags sold
First, we need to determine the number of bags for 27 pears;
Since they are packed in 3s


Hence:
9 bags were used for 27 pears;
After 5 bags were sold, we have:


Recall that the pears are packed in 3s
So:


<h3>
Answer: C) 2.47 cm</h3>
=====================================================
Explanation:
We have 81 cm^3 of clay. Divide this among the 20 students and each gets 81/20 = 4.05 cm^3 of clay
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The volume of a cone is
V = (1/3)*pi*r^2*h
Solving for h gets us
3V = pi*r^2*h
(3V)/(pi*r^2) = h
h = (3V)/(pi*r^2)
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The diameter is 2.5 cm which cuts in half to 1.25 cm, so this is the radius.
We'll plug this radius in, along with V = 4.05 and pi = 3.14
h = (3V)/(pi*r^2)
h = (3*4.05)/(3.14*(1.25)^2)
h = 2.4764
This value is approximate. Rounding down to the nearest hundredth gets us 2.47
We round down because rounding up to 2.48 will lead to a volume larger than 4.05