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
AVprozaik [17]
3 years ago
9

What multiplies to -1 and adds to 2

Mathematics
1 answer:
jok3333 [9.3K]3 years ago
5 0
    xy = -1
x + y = 2

  x + y = -2
- x         - x
        y = -x - 2

                           xy = -1
                  x(-x + 2) = -1
              x(-x) + x(2) = -1
                   -x² + 2x = -1
                         + 1   + 1
-x² + 2x + 1 = 0
-1(x²) - 1(-2x) - 1(-1) = 0
           -1(x² - 2x - 1) = 0
                     -1           -1
                x² - 2x - 1 = 0
x = -(-2) ± √((-2)² - 4(1)(-1))
                      2(1)
x = 2 ± √(4 - 4(-1))
                2
x = 2 ± √(4 + 4)
              2
x = 2 ± √(8)
           2
x = 2 ± 2√(2)
           2
x = 1 ± √(2)

               x + y = 2
  (1 ± √(2)) + y = 2
- (1 ± √(2))       - (1 ± √(2))
                     y = 1 ± √(2)
               (x, y) = (1 ± √(2), 1 ± √(2))

The numbers that multiply to -1 and add to 2 are 1 ± √(2).
You might be interested in
Joe has 45 minutes before he has to go to soccer practice he spends 20 minuets eating a snack and the rest of the time doing his
Alexeev081 [22]

Answer:

45=20+(x)

Step-by-step explanation:


6 0
4 years ago
Read 2 more answers
Complete parts (a) and (b) using the probability distribution below.
katen-ka-za [31]
Μ = (0×0.026) + (1×0.072) +(2×0.152) + (3×0.303) + (4×0.215) + (5×0.164) + (6×0.066) 
μ = 0 + 0.072 + 0.304 + 0.909 + 0.86 + 0.82 + 0.396
μ = 3.361 ≈ 3.4

We need the value of ∑X² to work out the variance
∑X² = (0²×0.026) + (1²×0.072) + (2²×0.152) + (3²×0.303) + (4²×0.215) + (5²×0.164) + (6²×0.066)
∑X² = 0+0.072+0.608+2.727+3.44+4.1+2.376
∑X² = 13.323

Variance = ∑X² - μ²
Variance  = 13.323 - (3.4)² = 1.763 ≈ 2

Standard Deviation = √Variance = √1.8 = 1.3416... ≈ 1.4

The correct answer related to the value of mean and standard deviation is the option D
<span>
An employee works an average of 3.4 overtime hours per week with a standard deviation of approximately 1.4 hours.</span>
7 0
3 years ago
Please help lol, im on a math test
Sveta_85 [38]
I know for sure it’s not B or D so I believe it is A.
5 0
3 years ago
What is the circumference of diameter of 2cm​
kicyunya [14]

a circle with a diameter of 2cm has a circumference of 6.28 cm

3 0
3 years ago
Help geometry B, the last option is 260 degrees
Leto [7]

Answer:

Q + S = 360 - 55 - 45 = 260

Q = S

=> Q = 260/2 = 130

C is correct

5 0
3 years ago
Other questions:
  • There are 6 rows with 18 chairs in each row. In the center of the chairs, 4 rows of 6 chairs are brown. The rest of the chairs a
    14·1 answer
  • HELP ME For which function will both ordered pairs (3, 6) and (4, 8) be solutions?
    6·1 answer
  • To improve his basketball skills, Troy decides to practice six times as many free throws and four times as many jump shots every
    10·2 answers
  • Really need help on these two math questions ??
    8·1 answer
  • PLEASE HELP, 46 PTS!!!! ANSWER QUICKLY AND WITH FULL REPONCE AND SHOW UR WORK!!
    8·1 answer
  • If you can answer 5 questions in an hour, how many questions can you complete in 3 hours? HINT: Use the proportion 5 questions :
    15·1 answer
  • Write a quadratic equation with the given roots write the equation in the form ax^2+bx+c=0 where a,b,and c are integers -5/4 and
    9·1 answer
  • Find the surface area of this right rectangular prism. Dimensions are in inches.<br> 3, 2, and 4
    12·1 answer
  • What is the following product? 3^sqr4 * sqr3​
    9·1 answer
  • PLEASE HELP ASAP I WILL BRAINLIEST
    5·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!