Answers
Answer:
(2.83 , 1 , 4)
Step-by-step explanation:
[tex]2x+2y-z=4\\4x-2y-2z=2\\3x+3y-4z=-4\\[/tex]
Rewrite these equations in matrix form
[tex]\left[\begin{array}{ccc}2&2&-1\\4&-2&-2\\3&3&-4\end{array}\right] \left[\begin{array}{ccc}x\\y\\z\end{array}\right]=\left[\begin{array}{ccc}4\\2\\-4\end{array}\right] \\[/tex]
we can write it like this,
[tex]AX=B\\X=A^{-1}B[/tex]
so to solve it we need to take the inverse of the 3 x 3 matrix A then multiply it by B.
We get the inverse of matrix A,
[tex]A^{-1}=\left[\begin{array}{ccc}7/15&1/6&-1/5\\1/3&-1/6&0\\3/5&0&-2/5\end{array}\right] \\[/tex]
now multiply the matrix with B
[tex]X=A^{-1}B\\\\\left[\begin{array}{ccc}x\\y\\z\end{array}\right] =\left[\begin{array}{ccc}7/15&1/6&-1/5\\1/3&-1/6&0\\3/5&0&-2/5\end{array}\right]\left[\begin{array}{ccc}4\\2\\-4\end{array}\right] \\\\\\\left[\begin{array}{ccc}x\\y\\z\end{array}\right] =\left[\begin{array}{ccc}2.83\\1\\4\end{array}\right] \\[/tex]
Related Questions
If the store paid $75 for a clarinet and sold it for $100, did the store mark up the price by 30%?
Answers
Answer:
No
Step-by-step explanation:
30% of $75 is $22.50 (0.3×75=22.5)
$75+$22.50=$97.50, not $100
So, the store did not mark up the price by 30% because the original price ($75) plus 30% more does not equal $100.
Answer:
no
Step-by-step explanation:
The cost, including sales tax, of a Ford Focus SE is $19,392.70. If the sales tax is 6%, find the cost of the car before the tax was added.
Answers
Answer:
the price before taxes was $18,229.13
Step-by-step explanation:
The length of a rectangle is 4 more than twice the width length. The perimeter is 28. What is the LENGTH?
Answers
Answer:
10[tex]\frac{2}{3}[/tex]
Step-by-step explanation:
Let the width length be x.
Width length = x
Length = 2x + 4
Perimeter = width + length + width + length
= x + 2x + 4 + x + 2x + 4
= 6x + 8
6x + 8 = 28
6x = 28 - 8
= 20
x = 20 ÷ 6
x = 3[tex]\frac{1}{3}[/tex]
Length (2x + 4) = 2(3[tex]\frac{1}{3}[/tex]) + 4
= 6[tex]\frac{2}{3}[/tex] + 4
= 10[tex]\frac{2}{3}[/tex]
Factor using grouping: x³+ 3x² + 5x = 15
Answers
1. Move all terms to one side of the equation, usually the left, using addition or subtraction.
2. Factor the equation completely.
3. Set each factor equal to zero, and solve.
4. List each solution from Step 3 as a solution to the original equation.
There are 32 desks in a room,
If x represents the number of rows of desks, which expression would equal the number of desks in each row?
32 x
32-x.
32 +x
32/x
Answers
32/x
Explanation
I think this is correct, the others wouldn’t make sense
The expression would equal the number of desks in each row is 32/x. Therefore, option D is the correct answer.
Given that, there are 32 desks in a room.
What is an expression?An expression is a combination of terms that are combined by using mathematical operations such as subtraction, addition, multiplication, and division.
Now, x represents the number of rows of desks.
The number of desks in each row = Total number of desks in a room / The number of rows of desks
= 32/x
The expression would equal the number of desks in each row is 32/x. Therefore, option D is the correct answer.
To learn more about an expression visit:
https://brainly.com/question/13947055.
#SPJ5
possible number of extrema a 4th degree polynomial could have is:
A. 3 or 1 extrema
B. 4 or 2 extrema
C. 5 extrema
D. none
Answers
Answer:
A
Step-by-step explanation:
You have $125 in a savings account and you deposit an equal amount into your account each week. After 5 weeks the account holds $170. Write an equation that represents the amount y (in dollars) of money in the account after x weeks.
Answers
Answer: 10x=y
Step-by-step explanation:
So if you subtract 170-125 you get 50. If you divide 50 by the 5 weeks you geat 10. So there is ten dollars a week going into the bank account.
What is the answer I need help pls
Answers
Answer:
The answers are,
-3, -7
-2, 4
0, 2
2, 8
3, 11
Step-by-step explanation:
You just plug in the domain values into the equation and solve for f(x), so your domain number is your x value and the y value(f(x) value) is the answer
These points are linear. Find the slope.
Answers
Answer:
5
Step-by-step explanation:
To find the slope of a line, you need to find the [tex]\frac{rise}{run}[/tex] between two points. I will be calculating the slope using the two points (2, 10) and (3, 15).
Slope = [tex]\frac{rise}{run}[/tex]
= [tex]\frac{15-10}{3-2}[/tex]
= 5
Are the following equations parallel, perpendicular, or neither? y= 3x - 1 and y =
-1/3x + 10 *
Parallel
Perpendicular
Neither
Answers
Answer:
Perpendicular
Step-by-step explanation:
5/12<__<3/4 what answer goes in the blank
Answers
Answer:
We have:
5/12<__<3/4
To complete the blank, we need to find a number that is larger than 5/12, but smaller than 3/4.
This is ratter easy, the first step would be to write both limits with the same denominator.
we can rewrite the upper one as:
3/4 = (3/3)*(3/4) = 9/12
Where we multiplied the numerator and denominator by the same number, 3.
Now we have:
5/12 < < 9/12
Then in the blank, we could input any number like:
5/12 + 1/12 = 6/12
6/12 is larger than 5/12, but smaller than 9/12
We also could use 7/12, or 8/12.
And those are the ones easy to find, actually, there are infinite numbers that can fill the blank.
Then to complete the answer we will write:
5/12 > 6/12 > 9/12
11. The table below shows the cost of comic books. Number of Comic Books Total Cost (dollars) 3 3.75 5 7 8.75 10 12.50 Based on the information in the table, which is the best prediction of the cost of 12 comic books?
Answers
Answer:
$15
Step-by-step explanation:
The unit rate or how much a comic book costs = total cost ÷ number of comic books
Using any given pair, let's use the first row (3, 3.75):
Unit rate = [tex] \frac{3.75}{3} = 1.25 [/tex]
This means a comic book cost $1.25.
Therefore, 12 comic books would cost:
12 × 1.25 = $15
Solve this simultaneous e
x + y = 26
3x + y = 56
Answers
Answer:
x= 15 and y= 11
Step-by-step explanation:
The goal here is to solve
x + y =26 and
3x + y =56 for the variables x and y.
First, let's work on your first equation, x + y =26
After this initial survey of the equations, the system of equations we'll set out to solve is:
x+y = 26 and 3x+y = 56
Let's start by solving x+y = 26 for the variable x.
Move the y to the right hand side by subtracting y from both sides, like this:
From the left hand side:
y - y = 0
The answer is x
From the right hand side:
The answer is 26-y
Now, the equation reads:
x = 26-y
To isolate the x, we have to divide both sides of the equation by the other variables
around the x on the left side of the equation.
and this is the final solution to your equation.
Next, let's solve 3x+y = 56 for the variable y.
Move the 3x to the right hand side by subtracting 3x from both sides, like this:
From the left hand side:
3x - 3x = 0
The answer is y
From the right hand side:
The answer is 56-3x
Now, the equation reads:
y = 56-3x
To isolate the y, we have to divide both sides of the equation by the other variables
around the y on the left side of the equation.
and this is the final solution to your equation.
Now, plug the earlier result, x=26-y, in for x everywhere it occurs in
y=56-3x.
This gives y=56-3(26-y). Now all we have to do is solve this for y,to have our first solution.
26-y evaluates to 26-y
Multiply 3 by 26-y
we multiply 3 by each term in 26-y term by term.
This is the distributive property of multiplication.
Multiply 3 and 26
1
3 × 26 = 78
Multiply 3 and -y
Multiply 1 and y
The y just gets copied along.
y
3 × -y = -3y
3*(26-y) evaluates to 78-3y
56 - 78 = -22
The answer is -22+3y
56-3*(26-y) evaluates to -22+3y
Move the 3y to the left hand side by subtracting 3y from both sides, like this:
From the left hand side:
y - 3y = -2y
The answer is -2y
From the right hand side:
3y - 3y = 0
The answer is -22
Now, the equation reads:
-2y = -22
To isolate the y, we have to divide both sides of the equation by the other variables
around the y on the left side of the equation.
The last step is to divide both sides of the equation by -2 like this:
To divide y by 1
The y just gets copied along in the numerator.
The answer is y
-2y ÷ -2 = y
-22 ÷ -2 = 11
The solution to your equation is:
y = 11
Lastly, to find the solution for x, we plug this answer for y into the earlier result that
x=26-y.
This gives x=26-(11). Now, simplify this.
26-(11) evaluates to 15
x= 15
So, the solutions to your equations are:
x= 15 and y= 11
Answer:
(15, 11 )
Step-by-step explanation:
Given the 2 equations
x + y = 26 → (1)
3x + y = 56 → (2)
Subtract (1) from (2) term by term to eliminate y, that is
2x = 30 ( divide both sides by 2 )
x = 15
Substitute x = 15 into either of the 2 equations and solve for y
Substituting into (1)
15 + y = 26 ( subtract 15 from both sides )
y = 11
solution is (15, 11 )
A boat traveled 54 km with the stream and 42 km against the stream spending a total of as much time as it would spend while travelling 96 km in a lake. Find the speed of boat while it is travelling in the lake, if the current of the river is 3 km/hour.
Answers
Answer:
18 miles / hour
PLS ITS A TEST ILL GIVE BRAINLIEST the equation is y = -3x + 2
y=x-6
Answers
Luis wants to buy Jordans for 75.23. He saves 10.27 per month. Write an equation to solve how many months he'll need to save.
Answers
Answer:
75.23=10.27x
Step-by-step explanation:
x will represent how many months Luis will save and it will equal 75.23. To find the value of x, divide 10.27 on both sides and get x=7.32. That means Luis will need to earn 10.27 for 7.32 months to get Jordans.
Nick earns 3.5%
commission on every
car he sells. How much
would he earn if he sold
a $14.000 car?
Answers
The amount he would earn is $490.
What does multiplication mean?
Multiplication is the process of determining the product of a number. It is determined by following some mathematical processes. The sign used to represent multiplication is ×.
How much will he earn?Commission = 3.5% x $14,000
0.035 x $14,000 = $490
To learn more about multiplication, please check: https://brainly.com/question/13814687
Use the following function rule to find f(-7).
f(x) = 9x - 7
O 70
O-56
0 -70
56
Answers
A line includes the points (-8,8) and (6,4). Select the correct point slope form equations of this line. (Remember there can be more than one)
Group of answer choices
y-8=(-2/7)(x+8)
y+8=(-2/7)(x-8)
y-4=(-2/7)(x-6)
Answers
Answer:
y-8=(-2/7)(x+8) and y-4=(-2/7)(x-6)
Step-by-step explanation:
Point slope form equation: y - y₁ = m(x - x₁)
m is the same for all your answer choices, so you can disregard that part.
First point: (-8,8)
x₁ = -8; y₁ = 8
Plug those values into the point slope form equation and you get:
y-8=(-2/7)(x+8)
Do the same for the second point, and you get:
y-4=(-2/7)(x-6)
Answer:
first and third options
Step-by-step explanation:
The equation of a line in point- slope form is
y - b = m(x - a)
where m is the slope and (a, b) a point on the line
Calculate m using the slope- formula
m = [tex]\frac{y_{2}-y_{1} }{x_{2}-x_{1} }[/tex]
with (x₁, y₁ ) = (- 8, 8) and (x₂, y₂ ) = (6, 4)
m = [tex]\frac{4-8}{6+8}[/tex] = [tex]\frac{-4}{14}[/tex] = - [tex]\frac{2}{7}[/tex]
using (a, b ) = (- 8, 8 ), then
y - 8 = - [tex]\frac{2}{7}[/tex] (x - (- 8) ) , that is
y - 8 = - [tex]\frac{2}{7}[/tex](x + 8) ← first option
using (a, b ) = (6, 4 ), then
y - 4 = - [tex]\frac{2}{7}[/tex] (x - 6) ← third option
which number line correctly graphs the numbers in the list?
Answers
Answer:
the first option
Step-by-step explanation:
what is m% of n please help
Answers
m% of n would technically be some amount of n. To find m%, you would have to do n * 0.m to find your answer
I need this done quick pls.
Answers
Answer:
58º
Step-by-step explanation:
The sum of a triangle's interior angles is 180º. We know two interior angles, and we can solve from there: 180-(65+57)=180-65-57=180-180-122=58.
How to I write 1 2/3 as an improper fraction help ASAP
Answers
[ 5/3 ]
Which of the following slopes of a line passes through points (2, 3) and (4,7) ?
5
2
3
O
Answers
Answer:
2
Step-by-step explanation:
slope = (difference in y)/(difference in x)
slope = (7 - 3)/(4 - 2)
slope = 4/2 = 2
Answer: 2
James borrows $4,200 to pay his college tuition. He signs a 5-year simple interest loan. If the monthly payments are $78.40, what is the interest rate on the loan?
Answers
Answer:
2.4%
Step-by-step explanation:
Total amount of payments:
5 years * 12 months/year * $78.40/month =
= $4704.00
Amount of interest paid in 5 years:
$4704 - $4200 = $504
Amount of interest paid in 1 year:
$504/5 = $100.80
Annual percent rate of interest:
$100.80/$4200 * 100% = 2.4%
Answer: 2.4%
4t + 2u
w;t= 2 and u= 1
Answers
15
Step-by-step explanation:
4t + 2u²- u³
4×2=8
2×1=2²=8
1³=1
8+8-1
16-1=15
Expand the following expression by using the distributive method. 6(3b-4c)
Answers
given that 16 ounces equal 1 pound , how many ounces are in 6.7 pounds
Answers
Answer:107.2
Step-by-step explanation:
Answer:
107.2
Step-by-step explanation:
6 x 16 = 96
.7 x 16 = 11.2
add them to get 107.2
In a class of 12 boys and 8 girls, two students need to be chosen for classroom jobs.
What is the probability that Mary gets selected?
Answers
Answer:
55 percent chance or 11/20 or 0.55
Step-by-step explanation
A decking company estimates how many gallons of stain each deck requires before starting construction. Apart from knowing the total area of each deck, which additional quantity will allow the decking company to make an accurate estimation
Answers
Answer:
Concept: Engineering Statistics
To make accurate estimations they need the total volume of the area.Hence they need the area coverage by the selected stain.Solution: Are covered by each gallon of stain This provides an accurate representation to a significant figure.