Solutions
In Matrix we use initially based on systems of linear equations.The matrix method is similar to the method of Elimination as but is a lot cleaner than the elimination method.Solving systems of equations by Matrix Method involves expressing the system of equations in form of a matrix and then reducing that matrix into what is known as Row Echelon Form.<span>
Calculations
</span>⇒ <span>Rewrite the linear equations above as a matrix
</span>
⇒ Apply to Row₂ : Row₂ - 2 <span>Row₁
</span>
⇒ <span>Simplify rows
</span>
Note: The matrix is now in echelon form.
<span>The steps below are for back substitution.
</span>
⇒ Apply to Row₁<span> : Row</span>₁<span> - </span>5 Row₂
⇒ <span>Simplify rows
</span>
⇒ <span>Therefore,
</span>

<span>
</span>
1. You have the function 
2. You know that
with
, because the division by zero is not defined. So ,
for
where
is a integer number.
3. Then, to find the domain of the function given in the problem, you must make 
Where
is odd number.
4. Therefore:

5. Finally, the domain is: 
The answer is: 
Step-by-step explanation:
Name the total of pens purchased as x and the pencils as y... Make two equations and solve them. I also search for the pencils purchased in addition