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
Nostrana [21]
3 years ago
15

Solve using the elimination method: X-3y=7 3x + 3y=9

Mathematics
1 answer:
sergij07 [2.7K]3 years ago
7 0

Answer:

                        x=4\\\\y=-1

Step-by-step explanation:

Given Equation:

x-3y=7      Equation:1

3x + 3y=9     Equation:2

Dividing Equation:2 by '3' both the sides:

x+y=3      

or   x=3-y     Equation:3

Putting the vale of 'x' in Equation:1

                             x-3y=7

                          (3-y)-3y=7\\\\3-y-3y=7\\\\3-4y=7\\\\

Subtracting '3' both sides

                             -4y=7-3\\\\-4y=4

                                 y=\frac{4}{-4}

                                 y=-1

Putting value of 'y' in Equation:3

                                x=3-y

                                x=3-(-1)\\\\x=3+1\\\\x=4

The solution of the equations is :

                              x=4\\\\y=-1

You might be interested in
PLZ LOOK AT THE IMAGE AND PLZ TELL ME THE ANSWER I WILL GIVE BRAINLESS
raketka [301]

Answer:

a) Unit price :

  • 12 cupcakes for $29 = $2.42
  • 50 cupcakes for $129 = $2.58

Reasoning:

  • 12 cupcakes for $29 = $29 ÷ 12 cupcakes which gives 2.416666667 and if rounded off gives you $2.42.
  • 50 cupcakes for $129 = $2.58 accurately.

b) 12 cupcakes for $29 gives the lowest unit price as $2.42 is less than $2.58.

<em>I hope this answer will help you !!!!</em>

7 0
3 years ago
1. A pond has 85 frogs, 20% of the frogs are green the rest are orange, brown, and yellow. How many frogs are green?​
alexandr402 [8]

Answer:

17 green frogs

Step-by-step explanation:

You need to multiply the decimal form of 20% by 85.

To find the decimal form of a percent you take the decimal (20.00) and move it twice to the left (20.00 ---> .2000)

Now, multiply by .2 by 85

(.2)(85) = 17

Therefore, 17 frogs in the pond of 85 frogs are green

<em>Hope this helps!!</em>

<em>- Kay :)</em>

4 0
3 years ago
Which is the property that justifies the action?
lidiya [134]
A) Action: multiply both sides by 4. 

Have a look: 

(x/4)x4=16x4 
x=64 

As you can see, the value of x can be found by multiplying 4 on both sides.

Hope I helped :) 


4 0
3 years ago
Read 2 more answers
I have a 15ft x 36in (4.57m x 91 cm) pool and the mats i wanna buy are 20.5-in x 20.5-in. How many mats would i need to put unde
yuradex [85]

Answer:

you would need 4 matts

Step-by-step explanation:

4 0
3 years ago
What is the value of (-5)^4
butalik [34]

Answer:

625

Step-by-step explanation:

7 0
3 years ago
Other questions:
  • Are the following figures similar?
    11·1 answer
  • A watch company sells 35 watches each day. How many watches does the company sell in two weeks if it’s open every day
    7·2 answers
  • Can someone please help
    13·1 answer
  • If 2x+ 3y = 55 and 4x= y+ 47, find x − y.<br> Can you please explain with some details?
    12·1 answer
  • a town Pharmacy in hospital is doing it as a part of format of the town has a scale 18840.35 miles what is the distance between
    11·1 answer
  • Solve 3(x+6) - 4 = 6x + 2 x =
    11·1 answer
  • Por qué la merece ser utilizada en la enseñanza de la matemática​
    15·1 answer
  • -5x=-6<br> what is the value of x?
    15·2 answers
  • Which is the better buy?​
    9·1 answer
  • ∠A = ___∘<br> Round your answer to the nearest hundredth.
    13·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!