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
Alinara [238K]
3 years ago
13

1) What is the solution of the given system?

Mathematics
1 answer:
m_a_m_a [10]3 years ago
3 0

Answer:

1  x=-2.5  y = -5.5

2.  x=5  y=1

Step-by-step explanation:

1) What is the solution of the given system?

5x-y=-7

3x-y=-2

Multiply the second equation by -1

-1*(3x-y)=-1(-2)

-3x +y = 2


Now add the first equation to the modified second equation

5x-y=-7

-3x +y = 2

------------------

2x = -5

Divide each side by 2

2x/2 = -5/2

x = -2.5

Now we need to find y

-3x+y =2

-3(-2.5) +y =2

7.5 +y =2

Subtract 7.5 from each side

7.5 -7.5 +y =2-7.5

y = -5.5


2) what is the solution of the given system?

5x+7y=32

8x+6y=46

Divide the second equation by 2

8x/2+6y/2=46/2

4x+3y =23


Multiply the first equation by 4

4 (5x+7y)=32*4

20x+28y = 128


Now multiply the modified 2nd equation by -5

-5(4x+3y )=-5(23 )

-20x -15y = -115


Lets add the new equations together to eliminate x

20x+28y = 128

-20x -15y = -115

---------------------

      13y = 13

Divide each side by 13

13y/13 =13/13

y=1

Now substitute back in to find x

5x+7y=32

5x +7(1) =32

5x +7 =32

Subtract 7 from each side

5x+7-7 =32-7

5x =25

Divide by 5

5x/5 =25/5

x=5





You might be interested in
Stacy is thinking of a number which she calls N. She triples it and adds 10
Stolb23 [73]

Answer:

3N + 10

Step-by-step explanation:

4 0
2 years ago
Read 2 more answers
A random variableX= {0, 1, 2, 3, ...} has cumulative distribution function.a) Calculate the probability that 3 ≤X≤ 5.b) Find the
olchik [2.2K]

Answer:

a) P ( 3 ≤X≤ 5 ) = 0.02619

b) E(X) = 1

Step-by-step explanation:

Given:

- The CDF of a random variable X = { 0 , 1 , 2 , 3 , .... } is given as:

                    F(X) = P ( X =< x) = 1 - \frac{1}{(x+1)*(x+2)}

Find:

a.Calculate the probability that 3 ≤X≤ 5

b) Find the expected value of X, E(X), using the fact that. (Hint: You will have to evaluate an infinite sum, but that will be easy to do if you notice that

Solution:

- The CDF gives the probability of (X < x) for any value of x. So to compute the P (  3 ≤X≤ 5 ) we will set the limits.

                   F(X) = P ( 3=

- The Expected Value can be determined by sum to infinity of CDF:

                   E(X) = Σ ( 1 - F(X) )

                   E(X) = \frac{1}{(x+1)*(x+2)} = \frac{1}{(x+1)} - \frac{1}{(x+2)} \\\\= \frac{1}{(1)} - \frac{1}{(2)}\\\\= \frac{1}{(2)} - \frac{1}{(3)} \\\\=  \frac{1}{(3)} - \frac{1}{(4)}\\\\= ............................................\\\\=  \frac{1}{(n)} - \frac{1}{(n+1)}\\\\=  \frac{1}{(n+1)} - \frac{1}{(n+ 2)}

                   E(X) = Limit n->∞ [1 - 1 / ( n + 2 ) ]  

                   E(X) = 1

8 0
2 years ago
What is the answer?<br> 2500/x+20<br> =2500/(48.59)+20
sammy [17]
The answer would be 71.45
7 0
3 years ago
Add.<br> -3 + (-4) <br><br> And <br><br> 4 pluse (-3)
Softa [21]

Answer:

-6

Step-by-step explanation:

-3 + (-4) 4 + (-3) is -6 I hope that helps because that what I got

8 0
3 years ago
The length of a spring varies directly with the mass of an object that is attached to it. When a 30-gram object is attached, the
Yuri [45]
Hi.
your answer is s=3/10m
hope this helps!!!
9 0
3 years ago
Read 2 more answers
Other questions:
  • How do i solve 2//3x=12?
    15·2 answers
  • Help please help me
    12·1 answer
  • Can someone help me with this?
    13·1 answer
  • What’s the value of the expression x=5?
    14·1 answer
  • Find the magnitude and direction angle of the resultant vector.
    7·1 answer
  • What is the volume of a rectangular prism that has a length of 15 mm, a width of 11 mm, and a height of 4 mm?
    13·2 answers
  • Answer to a unit test in math grade 6
    6·2 answers
  • Need for a test rn help !!
    13·1 answer
  • Translate 4 left and then reflect over the y axis<br><br> Please hurry
    6·2 answers
  • A radioactive isotope has a rate of decay of 84%. that is, every day,
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!