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
Vedmedyk [2.9K]
3 years ago
15

If 3x^2+3y^2=42 and xy =-15.Find the value (x-y)^2

Mathematics
1 answer:
Alexxandr [17]3 years ago
4 0

Answer:

44

Step-by-step explanation:

Given, 3x^2 + 3y^2 = 42

=>3(x^2 + y^2) = 42 =>x^2 + y^2 = 42/3= 14

Thus,

= (x - y)^2

= x^2 + y^2 - 2xy

= (x^2 + y^2) - 2xy

= 14 - 2(-15)

= 14 + 30

= 44

You might be interested in
Perimeter of 40 triangles when the sides are all 1 cm long
Marianna [84]

Answer: 120 cm.

Step-by-step explanation: Each triangle has 3 sides, and each side is 1 cm. Multiply the number of sides for one triangle by the total number of triangles. 3 x 40=120. The perimeter is 120 cm.

7 0
3 years ago
In certain county, the number of charter schools is 4 less than twice the numbervof alternative schools. We know that there are
Vitek1552 [10]
1. Let's call the number of carter school: "x" and "y" the number of alternative school.  Then, you have that:

 - T<span>he number of charter schools is 4 less than twice the number of alternative schools.
</span> - T<span>here are 48 charter schools in the country.

 2. So, you have:

 x=2y-4  (i)

 x=48  (ii)

 3. Then, when you substitute x=48 into the equation (i), you obtain:
</span>
 x=2y-4
<span> 48=2y-4

 4. Now, you must clear "y, as below:

 48+4=2y
 2y=52
 y=52/2
 y=26
 </span><span>
 How many alternative schools are in the county?
</span><span>
 The answer is: There are 26 alternative schools.</span>
6 0
3 years ago
How do you get the average of something
kogti [31]
The mean is the average of the numbers. It is easy to calculate: add up all the numbers, then divide by how many numbers there are. In other words it is the sum divided by the count.
6 0
3 years ago
Read 2 more answers
Solve 77 = -7x using one step equations
fgiga [73]

Answer:

x=-11

Step-by-step explanation:

Divide both sides by -7, and you get -11

4 0
3 years ago
Read 2 more answers
What is the average for a half marathon time on a 35 year old man?
nevsk [136]
Average time for a 35 year old man to run half a marathon is 9:50:38
4 0
3 years ago
Other questions:
  • Apples lose 75% of their weight during drying. How many pounds of fresh apples do you need to pick in order to get 150 lb of dri
    8·1 answer
  • Multiply and simplify.
    5·1 answer
  • A school buys 200 calculators at a special price. x of them were scientific calculators at R89 a piece and the rest were financi
    5·2 answers
  • • Manuela has two boxes. The larger of the two boxes has dimensions of 15 cm
    5·1 answer
  • 5|x3 - 21 + 7 when x = -2.
    10·1 answer
  • Write to polynomial in standard form then name the polynomial based on its degree and number terms.
    15·1 answer
  • Please help a girl out :)
    8·2 answers
  • Your friend tells you that if you let him keep 50 of your Pokemon cards for a month, he will give you 1 card extra when he retur
    14·1 answer
  • -3a + 3 &gt; 33<br> +<br> -15 -14 -13 -12 -11 -10 9 -3
    6·1 answer
  • a librarian is interested in how many books an average visitor checks out. she keeps a tally of how many books are checked out b
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!