Answer:
44d+66
Step-by-step explanation:
Answer:
13 pencils.
Step-by-step explanation:
Let x be the pens and y be the pencils
Given:
Brian purchased pens for 75 cents each and pencils for 40 cents each he bought total of 22 writing utensils for $11.95.
Total pens and pencils is 22
So,
----------------(1)
And he bought all utensils for $11.95. and each pen for 75 cents and pencils for 40 cents.
------------(2)
solve equation 1 and equation 2 for x and y.
From equation 1.
![x+y=22](https://tex.z-dn.net/?f=x%2By%3D22)
----------------(3)
put y value in equation 2.
![0.75x+0.4(22-x)=11.95](https://tex.z-dn.net/?f=0.75x%2B0.4%2822-x%29%3D11.95)
![0.75x+0.4\times 22-0.4x=11.95](https://tex.z-dn.net/?f=0.75x%2B0.4%5Ctimes%2022-0.4x%3D11.95)
![0.75x+8.8-0.4x=11.95](https://tex.z-dn.net/?f=0.75x%2B8.8-0.4x%3D11.95)
![0.75x-0.4x=11.95-8.8](https://tex.z-dn.net/?f=0.75x-0.4x%3D11.95-8.8)
![0.35x=3.15](https://tex.z-dn.net/?f=0.35x%3D3.15)
![x=\frac{3.15}{0.35}](https://tex.z-dn.net/?f=x%3D%5Cfrac%7B3.15%7D%7B0.35%7D)
![x=9](https://tex.z-dn.net/?f=x%3D9)
Now substitute x value in equation 3.
![y=22-9](https://tex.z-dn.net/?f=y%3D22-9)
![y=13](https://tex.z-dn.net/?f=y%3D13)
So, he buy 13 pencils.
Next 7 days
amount needed-amount now=amount in each day
200-148=52
52 in 7 days
divide by 7
52/7=7.4285
round
7.43
need to earn about $7.43 each day
In a system of equations ax + b = 0, a≠ 0, the equation x = -b/a is referred as a non-trivial solution.
<h3>What is a system of equations?</h3>
A system of equations is when two or more variables are related, and equations are built to find the values of each variable.
The system Ax + b = 0 has the following solutions:
- The zeros, which is the trivial solution.
- x = -b/a, which is the non-trivial solution.
More can be learned about a system of equations at brainly.com/question/24342899
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