−3x−9y=−12
−3x+7y=4
solve for x

Answer:

[tex] \huge{ \boxed{ \boxed{ \sf{ \red{ \sf{x = 1}}}}}}[/tex]

Step - by - step explanation :

[tex] \underline{ \underline{ \sf{Solution}}} : [/tex]

USING ELIMINATION METHOD :

[tex] \sf{ - 3x - 9y = - 12}[/tex] ••••••• equation ( i )

[tex] \sf{ - 3x + 7y = 4}[/tex] ••••••• equation ( ii )

Subtracting equation ( ii ) from ( i )

Note that while subtracting equation ( ii ) from ( i ) , sign of each term of equation ( ii ) changes and hence becomes 3x - 7y = -4.

[tex] \sf{ \cancel{ - 3x} - 9y = - 12}[/tex]

[tex] \sf{ \cancel{3x} - 7y = - 4}[/tex]

_____________________

➺ [tex] \sf{ - 16y = - 16}[/tex]

➺ [tex] \sf{ \frac{ - 16y}{ - 16} = \frac{ - 16}{ - 16}} [/tex]

➺ [tex] \sf{y = 1}[/tex]

The value of y is 1. Since , we are asked to find the value of x , substituting the value of y in equation ( i) , we get :

➺ [tex] \sf{ - 3x - 9 \times 1 = - 12}[/tex]

➺ [tex] \sf{ - 3x - 9 = - 12}[/tex]

➺ [tex] \sf{ - 3x = - 12 + 9}[/tex]

➺ [tex] \sf{ - 3x = - 3}[/tex]

➺ [tex] \sf{ \frac{ - 3x}{ - 3} = \frac{ - 3}{ - 3}} [/tex]

➺ [tex] \sf{ x = \boxed{ \bold{ \red{ \sf{1}}}}}[/tex]

Hence , the value of x is 1 .

⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆

☞ [tex] \underline{ \sf{Extra \: Info}} : [/tex]

There are many methods to solve such simultaneous equations. They are :

⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆⋆

✑ Learn more :

Solve system of equations using elimination method :

https://brainly.com/question/20160304

What is the substitution method ?

https://brainly.com/question/15936865

Hope I helped ! ツ

Have a wonderful day / night ♡

▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁▁

18x -1 (-3x + 9) distributing a negative number (plz I need help I need to get this done ASAP)

Can some people of brainly do this stuff for my little cousin i dont know what i'm doing.

Gym A charges a $70 sign-up fee and an additional $20 per month. Gym B only charges a $10 sign-up fee, but charges
a $40 monthly membership fee.

MARKING BRAINLIEST ❤️
(PLZ HELP ACTUALLY...)

An electrician charges $15.00 per hour for an electrical job that requires more
than 4 hours to complete. For any job requiring 4 hours or less, there is a flat
charge of $50.75. If x represents the number of hours the job requires, write
an expression that gives the charge, in dollars, for a job requiring more than 3
hours to complete.

Plz help answer these questions

A pulley rotates through 107° in one minute. How many rotations does the pulley make in an hour!
The pulley makes rotations per hour.
(Simplify your answer. Round to the nearest whole number.)

Sally wants to save for a new cell phone. She opens a bank account with $40 and adds $20 each week. Which of the following equations can be used to determine how much she has after ‘w’ weeks?

Find the missing angles.
10°
55°
LO
x=
y =
Z=
o
X=
0
y=
o
Z=

At one farmer’s market, bananas cost $0.80 per pound. At another farmer’s market, bananas are sold in 5-pound bags for $4.50 per bag. Which explains how to find the better buy?
Divide 4.50 by 5 to find the unit rate for the 5-pound bag, and compare that number to $0.80 per pound.
Divide 0.80 by 5 to find the unit rate for the 5-pound bag, and compare that number to $0.80 per pound.
Multiply 4.50 by 5 to find the cost for 5 pounds, and compare to $4.50 per bag.
Multiply 4.50 by 0.80 to find the cost for 5 pounds, and compare to $4.50 per bag.

PLEASE ANSWER< WILL GIVE BRAINLY TO BEST ANSWER!?

♡
Perform the calculation then
round to the appropriate number
of significant digits.
5207 - 24.2
Hint: Look at the number that has the FEWEST sig figs to
determine how many sig figs should be in your answer.
(24.2 has 3 significant digits, so your answer should have
3 significant digits.)
Enter

Answer with explanation please. Thank youuu​
​

Tell which number is greater.

37/50, 37%

I NEED HELPPPPPPPPPPPPPPP

How much of the circle is shaded? Write your answer as a fraction in simplest form.
3/7 and 1/4

why is it not showing the graph

1) For a period of time, an island's population grows at a rate of 3.8% per year. If the current
population is 1543, what will the population be in 5.2 years?

6. Write the equation for the two functions and
compare the rates of change.
Function C
Function D
y
The Used Book
Store will pay $0.50
for each box of
hardcover books.
--2
4
0
2
4

A bookstore charges a standard rate for paperback or hardback books. The cost of a paperback book is 4 dollars less than the cost of a hardback book.​ Recently, one day of sales totaled ​$1065.10. That day the bookstore sold 51 paperback books and 47 hardback books. Write a system representing this situation. Use the graph to estimate the solution of the system. What does the solution mean in this​ situation? How much does each type of book​ cost? Use substitution to verify your solution.

The diagram shows the governing system of a municipal government.



What does the diagram show about the strong mayor system?

The city council is elected and the mayor is not.
The mayor is elected and the city council is not.
The mayor has more power than the city council.
The city council shares equal power with the mayor.

Sorry, but can someone PLEASE help me Change 2 3/16 to an exact decimal. I'll give you 15 points

how do I find the slope of a line from a table graph ​

PLEASE HELP! it’s would be really appreciated

a half of 48 divided by6multiplied by4 plus 3 minus 2
​

Rewrite the fraction in the sentence below as a percentage. In 2002, a popular company made 11/20 of its money online.​

please help me find the longest side in triangle ABC

if the gas station has 80 customers on Tuesday, how many customers can be predicted to get a Dr.pepper?

A catapult’s lever holds a cannonball. The lever is attached to a tightly held rope. When the rope is released, the lever springs forward and launches the cannonball. When the rope is held tightly, which form of energy does it possess?​

Look at pictureeeee look at picture

On a field trip they take busses and vans. Each bus holds 60 people and each van holds 10 people. If 390 people went on the trip and they took a total of 9 vehicles, how many of each type of vehicle did they take?