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
MaRussiya [10]
3 years ago
8

Solve the equation. x² + 6x+15=0

Mathematics
1 answer:
lara [203]3 years ago
3 0

Answer:

x = -3 + i√6 and x = -3 - i√6

Step-by-step explanation:

Let's apply the "completing the square" method to find the roots of this equation.

Take half of the coefficient 6 of x, square it and add this result to x^2 + 6x.  Then subtract the same quantity:

x^2 + 6x + 15 becomes

x^2 + 6x + 3^2 - 3^2 + 15 = 0

Rewriting the first three terms as the square of a binomial, we ge:

(x + 3)^2 - 9 + 15 = 0, which simplifies to:

(x + 3)^2 + 6 = 0, or (x + 3)^2 = -6

Taking the square root of both sides:

x + 3 = ±i√6

Then the two roots are complex:

x = -3 + i√6 and x = -3 - i√6

You might be interested in
Olivia spent $18.00 of the $21.00 from
nexus9112 [7]

Answer:

6/7

Step-by-step explanation:

18/21 dollars is simplified when you divide the fraction by 3 on each number. So you get 6/7 of her money was spent.

3 0
3 years ago
N/-1.5 = -1.2 DO NOT round the solution
wariber [46]
N = -1.5 * -1.2 = 1.8
3 0
3 years ago
Read 2 more answers
Marisa has 2 pennies, 4 nickels, and 5 dimes in her pocket. How many different arrangements are possible if she removes one coin
Radda [10]
-2 pennies, 4 nickels, 4 dimes
-2 pennies, 4 nickels, 3 dimes
-2 pennies, 4 nickels, 2 dimes

And so on. Do you kind of get the idea?
3 0
3 years ago
Read 2 more answers
Helooooo?!!!!! 30 whole points
pentagon [3]

Answer:

I believe C, or the answer you have chosen, is correct.

Step-by-step explanation:

In this question, we add like, AKA similar, terms.

There is nothing to match x^2, so we leave it alone and put it at the head of equation since it has the highest power:

x^2

There is nothing to match -x, so we also leave it alone and put it next to x^2, keeping its sign:

x^2 - x

We can add 1 and 5 to get 6, so we put 6 next to the -x to get our final equation:

x^2 - x + 6.

See how easy that was? :) Hope this helps you and you get a good grade on your test!!

Please rate my answer and give me Brainliest!!!!

Have an awesome rest of your day! :)

7 0
3 years ago
Find the value of y in the formula y = 5a – 3b + c, if a = 12, b = 4, and c = 8. A. 64 B. 56 C. 40 D. 80
Orlov [11]
<span>y = 5(12) - 3(4) + 8 
y = 60 - 12 + 8 
y= 56</span>
3 0
3 years ago
Read 2 more answers
Other questions:
  • Can someone explain how to solve this?
    6·1 answer
  • What is the length of the line?
    5·1 answer
  • Find the balance in the account after the given period. $4000 principle earning 3% compounded annually 6 years
    10·1 answer
  • PLEASE HELP NEEDS TO BE DONE TONIGHT HELP PLEASE ASAP!
    5·1 answer
  • 31/25x=-62 find the value of x
    7·1 answer
  • Solve: 8.2 = 3.4 + d d = _____
    7·1 answer
  • Estimate by rounding each term to 0. 1/2 or 1.<br> 5 1<br> 8 3
    7·1 answer
  • No need to explain the answer.
    11·2 answers
  • Ali bought 2 litre milk. he drank ⅖ litre of it. how much milk did ali has left?
    7·1 answer
  • Pfvr algm me ajuda nessa
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!