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
mixas84 [53]
3 years ago
10

Solve with matrices. 5x -3y = 18 and 2x + 7y = -1

Mathematics
1 answer:
muminat3 years ago
6 0

We'll use Cramer's rule for 2 equations:

ax + by = e

cx + dy = f

5x -3y = 18 a=5 b=-3 e=18

2x + 7y = -1 c=2 d=7 f=-1

denominator determinant (dn) = (a * d) - (c * b) = 5 * 7 - (2 * -3) = 41

x = [(e * d) - (f * b)] / dn

[18 * 7 - (-1 * -3)] / 41 =

123 / 41 = 3

y = [(a * f) - (c * e)] / dn

= (5 * -1) -(2 * 18) / 41 =

-41 / 41 = -1

Source:

1728.com/cramer.htm

You might be interested in
Find the discriminant of X^2+ 4x - 3 = 0
Drupady [299]

Answer:

2 real solutions

Step-by-step explanation:

Given a quadratic equation in standard form

ax² + bx + c = 0 ( a ≠ 0 ), then the discriminant is

Δ = b² - 4ac

• If b² - 4ac > 0 then 2 real and distinct solutions

• If b² - 4ac = 0 then 2 real and equal solutions

• If b² - 4ac < 0 then no real solutions

x² + 4x - 3 = 0 ← is in standard form

with a = 1, b = 4, c = - 3 , then

b² - 4ac = 4² - (4× 1 × - 3) = 16 - (- 12) = 16 + 12 = 28

Since b² - 4ac > 0 then the equation has 2 real and distinct solutions

5 0
3 years ago
Identify the sample space of the probability experiment: Answering a true or false question.
marusya05 [52]

Answer:

there are 5

Step-by-step explanation:

"im different"

5 0
2 years ago
What is the absolute value of Point C labelled on the number line? A number line with point A at coordinate -2.75, point B at co
lina2011 [118]

Answer:

2.25

Step-by-step explanation:

The value of point C is already positive, so nothing changes.

_____

The absolute value function changes negative numbers to positive ones (by multiplying by -1, or reflecting across the origin of the number line).

3 0
2 years ago
Why does multiplying by 10 shift each digit one place to the left?
Leto [7]

as we move down the list as we push the *digits* to the *left*through the decimal *point* *each* *number has been 10*. and so we can easily *multiply* or divide by *a* power of *10* because of our system of positional numeration. Each Place belongs to the next power of *10*.

6 0
3 years ago
For the following paired data, (1) Calculate the correlation coefficient, r, and (2) at the 0.05 significance level, determine w
expeople1 [14]

Answer:

Linear correlation exists

Step-by-step explanation:

Given the data :

X : | 2 4 5 6

Y : | 6 9 8 10

Using technology to fit the data and obtain the correlation Coefficient of the regression model,

The Correlation Coefficient, r is 0.886

To test if there exists a linear correlation :

Test statistic :

T = r / √(1 - r²) / (n - 2)

n = number of observations

T = 0.886 / √(1 - 0.886²) / (4 - 2)

T = 0.866 / 0.3535845

T = 2.449

Comparing Pvalue with α

If Pvalue < α ; Reject H0

Pvalue = 0.1143

α = 0.05

Pvalue > α ; We reject the null and conclude that linear correlation exists

7 0
3 years ago
Other questions:
  • You roll a pair of fair six-sided dice. The sample space of 36 possible outcomes is shown below. Based on this information, answ
    15·1 answer
  • Name two congruent angles that measure 15
    5·1 answer
  • What is a conversion factor that you can use to convert gallons to pints?
    10·1 answer
  • A diffraction grating is illuminated with yellow light. The diffraction pattern seen on a viewing screen consists of three yello
    15·1 answer
  • Gegygwugduwbudbwbdubwudbuwh7fh7whf8hw8hf8hw8hf8e​
    13·2 answers
  • In a survey 6% of adults did not<br> know how to ride a bike. What<br> percentage could ride?
    7·2 answers
  • a maintence worker is replacing worn rope on 6 flagpoles.The worker needs 40 feet of rope for each flagpole.At the hardware stor
    9·1 answer
  • PLEASE HELP!!!! i will give branliest
    12·1 answer
  • Which of the following can be used to solve for X
    13·1 answer
  • Sam and Jack received a cash voucher and they divided the amount equally between them.
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!