Answer:
x= -3 and y= 0
Step-by-step explanation:
5x+2y=-15
<u>2x-2y=-6 </u>
<u>7x =-21</u>
x= -3
Putting value of x in equation 1
5(-3) +2y=-15
-15+2y= -15
2y= 0
y= 0
This can be solved with the help of matrices
In matrix form the above equations can be written in the form
![\left[\begin{array}{ccc}5&2\\2&-2\/\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D5%262%5C%5C2%26-2%5C%2F%5Cend%7Barray%7D%5Cright%5D)
![\left[\begin{array}{ccc}x\\y\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Dx%5C%5Cy%5C%5C%5Cend%7Barray%7D%5Cright%5D)
= ![\left[\begin{array}{ccc}-15\\-6\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-15%5C%5C-6%5C%5C%5Cend%7Barray%7D%5Cright%5D)
Let
= A = X and = B
Then AX= B
or X= A⁻¹ B
where A⁻¹= adj A/ ║A║ where mod A≠ 0
adj A= ![\left[\begin{array}{ccc}-2&-2\\-2&5\/\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-2%26-2%5C%5C-2%265%5C%2F%5Cend%7Barray%7D%5Cright%5D)
║A║= ( 5*-2- 2*2)= -10-4= -14≠0
X= A⁻¹ B
=- 1/14
=- 1/14 ![\left[\begin{array}{ccc}-2*-15&+ -2*-6\\-2*-15&+ 5*-6\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-2%2A-15%26%2B%20-2%2A-6%5C%5C-2%2A-15%26%2B%205%2A-6%5C%5C%5Cend%7Barray%7D%5Cright%5D)
=- 1/14 ![\left[\begin{array}{ccc} 30&+12\\30&+-30\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D%2030%26%2B12%5C%5C30%26%2B-30%5C%5C%5Cend%7Barray%7D%5Cright%5D)
=- 1/14 ![\left[\begin{array}{ccc}42\\0\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D42%5C%5C0%5C%5C%5Cend%7Barray%7D%5Cright%5D)
= ![\left[\begin{array}{ccc}-42/14\\0/-14\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-42%2F14%5C%5C0%2F-14%5C%5C%5Cend%7Barray%7D%5Cright%5D)
= ![\left[\begin{array}{ccc}-3\\0\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-3%5C%5C0%5C%5C%5Cend%7Barray%7D%5Cright%5D)
From here x= -3 and y= 0
Solution Set = [(-3,0)]
Answer:
4x(3x+7)
Step-by-step explanation:
Dividing the number of tires that should be installed per day which is 400 by the number of working hours which is 8 will give us 50 tires per hour. Assuming that the same mistake will take toll on the workers such that they will have 1 tire mistakenly installed in an hour, they will have 8 erroneous tires in a day. Multiplying this by 5 to make the answer per week will give 40. Out of the 400 x 5 = 2000 tires. The answer would be 2000 - 40 which is equal to 1940. The assumption must be valid.
[~Answer~] (3.):
Hello there! I'm Avery, and I'm here to help you! I mostly believe the answer <em>Could be: (the answer is in the screenshot. I couldn't write it, so I typed it.) </em>
<em>
</em>+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
[~Answer Explanation~]:
1:
Combine multiplied terms into a single fraction
2:
Find common denominator
3:
Combine fractions with common denominator
4:
Multiply the numbers
5:
Re-order terms so constants are on the left
6:
Combine exponents
7:
Rearrange terms
8:
Find common denominator
9:
Combine fractions with common denominator
10:
Re-order terms so constants are on the left
11:
Rearrange terms
12:
Multiply all terms by the same value to eliminate fraction denominators
13:
Cancel multiplied terms that are in the denominator
14:
Distribute
15:
Move terms to the left side
16:
Distribute
17:
Subtract the numbers
18:
Rearrange terms
19:
Use the quadratic formula
20:
Simplify
21:
Separate the equations
22:
Solve
Answer: z = 
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
[~Last Messages~]:
Okay, I really hope my answer is correct.
I am truly sorry if it's wrong :(
Have a great morning, afternoon, or night. <333
<u><em>[-!AveryIsSomeHowAlive!-}</em></u>
-2x=15-7y
x=-7.5+3.5y
-3x-8y=4
-3(7.5+3.5y)-8y=4
-22.5-10.5y-8y=4
-22.5-18.5y=4
-18.5y=4+22.5
-18.5y=26.5
y=-53/35
the fraction might not be in lowest terms.
