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
charle [14.2K]
1 year ago
12

In order to solve the following system of equations by addition, which of the

Mathematics
2 answers:
hodyreva [135]1 year ago
6 0
  • 4x-2y=7
  • 3x-3y=15

The step is

Multiply 3 with eq(1) and multiply -4 with eq(3)

Then x coefficient becomes 12 and -12 respectively so you can cancel then out

Pavlova-9 [17]1 year ago
3 0

Answer:

Multiply the top equation by -3 and the bottom equation by 2

Step-by-step explanation:

Given <u>system of equations</u>:

\begin{cases}4x-2y=7\\3x-3y=15 \end{cases}

To solve the given system of equations by addition, make one of the variables in both equations <u>sum to zero</u>.  To do this, the chosen variable must have the <u>same coefficient</u>, but it should be <u>negative</u> in one equation and <u>positive</u> in the other, so that when the two equations are added together, the variable is <u>eliminated</u>.

<u>To eliminate the </u><u>variable y</u>:

Multiply the top equation by -3 to make the coefficient of the y variable 6:

\implies -3(4x-2y=7) \implies -12x+6y=-21

Multiply the bottom equation by 2 to make the coefficient of the y variable -6:

\implies 2(3x-3y=15) \implies 6x-6y=30

Add the two equations together to <u>eliminate y</u>:

\begin{array}{l r r}& -12x+6y= &-21\\+ & 6x-6y= & 30\\\cline{1-3}& -6x\phantom{))))))} = & 9\end{array}

<u>Solve</u> for x:

\implies -6x=9

\implies x=-\dfrac{9}{6}=-\dfrac{3}{2}

<u>Substitute</u> the found value of x into one of the equations and <u>solve for y</u>:

\implies 3\left(-\dfrac{3}{2}\right)-3y=15

\implies -\dfrac{9}{2}-3y=15

\implies -3y=\dfrac{39}{2}

\implies y=-\dfrac{39}{2 \cdot 3}

\implies y=-\dfrac{13}{2}

Learn more about systems of equations here:

brainly.com/question/27868564

brainly.com/question/27520807

You might be interested in
A ​used-boat dealership buys a boat for ​$2800 and then sells it for ​$4000. What is the percent​ increase?
Rudik [331]

Answer:

Step-by-step explanation:

percent increase = increase divided by original number x 100

                           

increase is the difference between the two numbers...

new number - original number.....4000 - 2800 = 1200

percent increase = (1200 / 2800) x 100

                            = 0.42857 (round to .4286) x 100

                             = 42.86 %.....if you need it rounded to the nearest percent, it      would be 43% increase

6 0
3 years ago
Determine the value of x and y and the measure of
artcher [175]
You need to finish the question
6 0
3 years ago
Express 3080 as a product of prime factors
n200080 [17]
Prime Factors of 3080 =2, 2, 2, 5, 7, 11

Which is the same as = 23 x 5 x 7 x 11

Prime Factors Tree of 3080

3080
/ \
2 1540
/ \
2 770
/ \
2 385
/ \
5 77
/ \
7 11
/ \
11 1
4 0
3 years ago
What is the value of x?
Makovka662 [10]

Answer:

A-100

Step-by-step explanation:

Use the Pythagorean therom.

a^2+b^2=c^2

6^2+8^2=c^2

36+64=100.

Hope this helps. Kinda confused me.


4 0
3 years ago
Pls help me with this i will give brainlyest to whoever answers first
Ksivusya [100]

Answer:

Senate

Step-by-step explanation:

Senate

6 0
3 years ago
Other questions:
  • Aaron invested $4000 in an account that paid an interest rate r compounded quarterly. After 10 years he has $5809.81. The compou
    8·2 answers
  • What is the prime factorization of 45?
    7·1 answer
  • A message center receives calls from 6 p.m. until 6 a.m. Typically, 50% of the calls come in between 6 p.m. and 9 p.m.; 25% of t
    7·1 answer
  • (b+3)(b^2-5b-5b-7) how to simplify
    7·1 answer
  • A buyer anticipates a house payment of $1,000 per month, with monthly homeowner association fees of $150. The buyer also has a c
    13·1 answer
  • 15 POINT!!!!!!!!!!!!!!!!!!!! Using the graph of f(x) and g(x), where g(x) = f(k⋅x), determine the value of k. Graph of two lines
    15·2 answers
  • What is the similarity ratio of two cubes with volumes of 125 cubic meters and 216 cubic meters?
    6·1 answer
  • Find the volume of each figure. Round to the nearest tenth if necessary.​
    9·1 answer
  • Which is the best way to fix the following run on sentence
    6·1 answer
  • What is the y-coordinate of the point that divides the directed line segment from J to K into a ratio of 5:1? y = (StartFraction
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!