Step-by-step explanation:
The elements of matrices are represented in the form
Here r is the row number and c is the column number.
Given matrix is:
![A = \left[\begin{array}{ccc}3&6&9\\2&4&8\end{array}\right]](https://tex.z-dn.net/?f=A%20%3D%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D3%266%269%5C%5C2%264%268%5Cend%7Barray%7D%5Cright%5D)
The elements of matrix will be represented by a_{r,c}
We have to find 
Which means that the first row and third column.
The first row is: 3 6 9 and the element in third column is: 9
So,
Keywords: Matrices, Elements
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<span>Simplifying
0x + 7 + 5x = 2x + 30 + 40
Anything times zero is zero.
0x + 7 + 5x = 2x + 30 + 40
Combine like terms: 0 + 7 = 7
7 + 5x = 2x + 30 + 40
Reorder the terms:
7 + 5x = 30 + 40 + 2x
Combine like terms: 30 + 40 = 70
7 + 5x = 70 + 2x
Solving
7 + 5x = 70 + 2x
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '-2x' to each side of the equation.
7 + 5x + -2x = 70 + 2x + -2x
Combine like terms: 5x + -2x = 3x
7 + 3x = 70 + 2x + -2x
Combine like terms: 2x + -2x = 0
7 + 3x = 70 + 0
7 + 3x = 70
Add '-7' to each side of the equation.
7 + -7 + 3x = 70 + -7
Combine like terms: 7 + -7 = 0
0 + 3x = 70 + -7
3x = 70 + -7
Combine like terms: 70 + -7 = 63
3x = 63
Divide each side by '3'.
x = 21
Simplifying
x = 21</span>
12 ounces = to .75 lbs
5/8lbs = 10 ounces
12 ounces
