Answer:
A
Step-by-step explanation:
This explanation mostly depends on what you're learning right now. The first way would be to convert this matrix to a system of equations like this.
g + t + k = 90
g + 2t - k = 55
-g - t + 3k = 30
Then you solve using normal methods of substitution or elimination. It seems to me that elimination is the quickest method.
g + t + k = 90
-g - t + 3k = 30
____________
0 + 0 + 4k = 120
4k = 120
k = 30
No you can plug this into the first two equations
g + t + (30) = 90
g + t = 60
and
g + 2t - (30) = 55
g + 2t = 85
now use elimination again by multiplying the first equation by -1
g + 2t = 85
-g - t = -60
_________
0 + t = 25
t = 25
Now plug those both back into one of the equations. I'll just do the first one.
g + (25) + (30) = 90
g = 35
Therefore, we know that Ted spent the least amount of time on the computer.
The second method is using matrix reduction and getting the matrix in the row echelon form, therefore solving using the gauss jordan method. If you would like me to go through this instead, please leave a comment.
The cost of book has to be less than or equal to 26.39.
The amount of money Elena can buy has to be less than or equal to $30. Thus, the inequality sign to be used is the less than or equal to sign.
(1 + tax)cost of books + cost of bus fare ≤ value of the gift
1.08c + 1.5 ≤ 30
In order to determine the maximum cost of books, take the following steps:
Combine similar terms
1.08c ≤ 30 - 1.5
Add similar terms together
1.08c ≤ 28.50
Divide both sides of the equation by 1.08
c ≤ 28.50 / 1.08
c ≤ 26.39
To learn more about taxes, please check: brainly.com/question/25311567
Answer:
x ≥ 12
Step-by-step explanation:
Step 1: subtract 2 from both sides
Now you have; -3/4 x ≤ -9
Step 2: divide both sides by -3/4
Now you have x ≥ 12
(when dividing an inequality by a negative you have to flip the sign)
Therefore the answer is x ≥ 12
