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
UkoKoshka [18]
3 years ago
7

Solve the simultaneous equations3x - 4y = 189x + 2y = 12​

Mathematics
2 answers:
NNADVOKAT [17]3 years ago
5 0

3x - 4y = 18

9x + 2y = 12​

Solve for x in the first equation.

3x - 4y = 18

3x = 18 + 4y

x = (18 + 4y)/3

x= 6+4/3y

Put x as 6+4/3y in the second equation and solve for y.

9x + 2y = 12​

9(6+4/3y)+2y =12

12y+54+2y=12

14y+54=12

14y=12-54

14y=-42

<h2>y = - 3</h2>

Put y as -3 in the first equation to solve for x.

3x - 4y = 18

3x - 4(-3) = 18

3x+12=18

3x=18-12

3x=6

<h2>x = 2</h2>
Nikolay [14]3 years ago
3 0

Answer:

x = 2 and y = -3

Step-by-step explanation:

Multiply the first equation by 3 to make the x coefficients the same for both equations.

It becomes 9x - 12y = 54. (eqn 1)

and 9x + 2y = 12 (eqn 2)

subtract eqn 2 from eqn 1

9x - 9x - 12y -2y = 54 - 12

-14y = 42

dividing both sides by -14

y = -3

Substituting y as -3 in eqn 1

9x - 12(-3) = 54

9x + 36 = 54

9x = 54 - 36

9x = 18

dividing both sides by 9

x = 2

You might be interested in
1. What is the distributive law for real numbers a,b,c? A(b+c)=ab+ac (a+b)c=ac+bc (a+c)b=ab+cb All of the answer choices are cor
Andre45 [30]

Answer:

Step-by-step explanation:

<h3>tdaso</h3>
3 0
3 years ago
The key factors in determining the accuracy of an opinion poll are
MAVERICK [17]

Answer:

Option B

Step-by-step explanation:

In this case, rather than tell you why option B is correct, let me tell you why the other options are incorrect.

As you can see, all the options share one common answer and is the sample size, so, this is one of the first key factors.

In option A, you have same percentage of men and women. This is not true, because the poll can be used only by men or women, so the percentage of men and women are not factors here.

In option C, we only have the population size. This is not accurate because, because we can determine the accuracy of the poll whether you have a population size of 20 people, and get the same accuracy with a population size of 100.

In option D, it's not neccesary the timeline, because you can take the accuracy in one time, and the result will be the same after time, for example, suppose the opinion poll is about politic, and the question is whether you liked Trump at the beggining or not. You could answer no at first, and say no again, 5 years later if the question remains the same.

Finally option E, you don't need to know the nature of the sampling process to get the accuracy of the poll.

The most important here is which method was taken to do the poll, for example, if it was oral, written or other method.

6 0
4 years ago
In how many different ways can the letters in the word PAYMENT be arranged if the letters are taken 6 at a time?
podryga [215]

Answer:

D.

Step-by-step explanation:

7

PAYMENT

1234567

THERE ARE 7 ELEMENTS

8 0
3 years ago
Figure STOP is reflected about the y-axis to obtain figure STO′P: A coordinate plane with two quadrilaterals is shown. Figure ST
gogolik [260]

Answer:

Figure STOP is congruent to figure S′T′O′P′.

Step-by-step explanation:

I just took the test

6 0
4 years ago
Solve using the square root method X2=25<br>​
aleksandrvk [35]

Answer:

Square root =

remember :

\boxed {x^2 = \pm a}

x² = ± a

x = ña

.

x = ñ25

x = ±5

• x = 5 and -5

8 0
3 years ago
Read 2 more answers
Other questions:
  • What are the possible numbers of positive, negative, and complex zeros of f(x) = -3x^4 + 5x^3 - x^2 + 8x + 4?
    9·1 answer
  • Find 15% tip for $32
    9·1 answer
  • Carla has built the figure below by using congruent cubes . What is the total volume of the figure she built
    7·1 answer
  • I WILL GIVE YOU A BRILLIANT
    10·2 answers
  • The Turner family and the James family each used their sprinklers last summer. The water output rate for the Turner family's spr
    8·1 answer
  • A minor league baseball pitcher threw 18 strikes in his first 40 pitches for a strike percentage of 45%. He wants to raise this
    10·1 answer
  • Jill is using a map of her town to determine how far the park is from school. The map does not have a scale, but Jill knows her
    14·2 answers
  • What type of function is f (x)
    5·1 answer
  • Factor by using the difference of two squares formula.<br> x²-9<br><br> PLEASE HELP!
    15·1 answer
  • 32) Convert this fraction to a decimal number: 4/10
    12·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!