1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Ksenya-84 [330]
2 years ago
5

Solve the following system. Please show me how you did it.

Mathematics
1 answer:
Andrej [43]2 years ago
4 0

Answer:

x = 3, y = 4 and z = -5.

Step-by-step explanation:

Use the elimination method:

-3x + 2y + z = -6...........(1)

x + 3y + 2z = 5..............(2)

4x + 4y + 3z = 13..........(3)

Multiply the first equation by -2:

6x - 4y - 2z = 12   Add this to equation (2):

7x  - y  = 17...........(4)

Now Multiply equation (2) by 3 and equation (3) by -2

3x + 9y + 6z = 15 ............(5)

-8x - 8y - 6z = -26............(6)   Adding (5) + (6):

-5x + y = -11..........(7)

Now Add (7) and (4):

2x = 6

x = 3.

Now  substitute for x in (4):

7(3) - y = 17

-y = 17 - 21 = -4

y = 4.

Finally substitute for x and y in equation (3) to find z:

4(3) + 4(4)  +3z = 13

3z = 13 - 12 - 16 = -15

z = -5.

You might be interested in
Help me plz and explain
Verdich [7]
58.50 - 45 = 13.50

13.50 / 45 x 100 = 30%

answer: mark up 30%
8 0
3 years ago
A person invests 10000 dollars in a bank. The bank pays 5.5% interest compounded
Blizzard [7]

Answer:

Step-by-step explanation:

4000 years

8 0
2 years ago
HELP NOW PLSSS enter your answer as mixed number and simpliflied, -4 1/2 x 2 1/2
nekit [7.7K]

Answer:

-11 1/4

Step-by-step explanation:

8 0
3 years ago
Given a dilation around the origin, what is the scale factor K?<br><br> D o, K = (2,4) → (3,6)
fenix001 [56]

Answer: 3/2

Step-by-step explanation:

5 0
3 years ago
Solve the equation by graphing. If exact roots cannot be found, state the consecutive integers between which the roots are locat
zavuch27 [327]

Answer:

The equation contains exact roots at x = -4 and x = -1.

See attached image for the graph.

Step-by-step explanation:

We start by noticing that the expression on the left of the equal sign is a quadratic with leading term x^2, which means that its graph shows branches going up. Therefore:

1) if its vertex is ON the x axis, there would be one solution (root) to the equation.

2) if its vertex is below the x-axis, it is forced to cross it at two locations, giving then two real solutions (roots) to the equation.

3) if its vertex is above the x-axis, it will not have real solutions (roots) but only non-real ones.

So we proceed to examine the vertex's location, which is also a great way to decide on which set of points to use in order to plot its graph efficiently:

We recall that the x-position of the vertex for a quadratic function of the form f(x)=ax^2+bx+c is given by the expression: x_v=\frac{-b}{2a}

Since in our case a=1 and b=5, we get that the x-position of the vertex is: x_v=\frac{-b}{2a} \\x_v=\frac{-5}{2(1)}\\x_v=-\frac{5}{2}

Now we can find the y-value of the vertex by evaluating this quadratic expression for x = -5/2:

y_v=f(-\frac{5}{2})\\y_v=(-\frac{5}{2} )^2+5(-\frac{5}{2} )+4\\y_v=\frac{25}{4} -\frac{25}{2} +4\\\\y_v=\frac{25}{4} -\frac{50}{4}+\frac{16}{4} \\y_v=-\frac{9}{4}

This is a negative value, which points us to the case in which there must be two real solutions to the equation (two x-axis crossings of the parabola's branches).

We can now continue plotting different parabola's points, by selecting x-values to the right and to the left of the x_v=-\frac{5}{2}. Like for example x = -2 and x = -1 (moving towards the right) , and x = -3 and x = -4 (moving towards the left.

When evaluating the function at these points, we notice that two of them render zero (which indicates they are the actual roots of the equation):

f(-1) = (-1)^2+5(-1)+4= 1-5+4 = 0\\f(-4)=(-4)^2+5(-4)_4=16-20+4=0

The actual graph we can complete with this info is shown in the image attached, where the actual roots (x-axis crossings) are pictured in red.

Then, the two roots are: x = -1 and x = -4.

5 0
3 years ago
Other questions:
  • -3+5+6g=11-3g help asap please
    7·1 answer
  • write the integer that represents a depth of 128 feet below sea level. then write the opposite of that integer.
    13·1 answer
  • If the range of the function f(x) = 4x – 3 is {11.4, 15, 17, 29}, what is its domain?
    15·2 answers
  • Pls answer its 2 in the morning I’m tryna get sleeppp
    9·1 answer
  • Can u plz help me with this question?​
    15·1 answer
  • 30,14,25,,13,33,14 the missing value is?
    12·1 answer
  • 3. A manufacturing process produces integrated circuit chips. Over the long run, the fraction of bad chips produced by the proce
    15·1 answer
  • Change 7 4/5 to an improper fraction
    7·2 answers
  • What is the supplement of a 30° angle?
    10·2 answers
  • Clarice was late paying her credit card bill of $249. She was charged a 5% late fee. What was the amount of the late fee?
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!