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alukav5142 [94]
3 years ago
11

X^2+2x+9=0 please?!​

Mathematics
2 answers:
Nadusha1986 [10]3 years ago
5 0

Answer:

D

Step-by-step explanation:

Given a quadratic equation in standard form : ax² + bx + c = 0

We can solve for x using the quadratic formula

x² + 2x + 9 = 0 ← is in standard form

with a = 1, b = 2 and c = 9

x = ( - 2 ± \sqrt{2^2-(4(1)(9)}) / 2

  = ( - 2 ± \sqrt{4-36}) / 2

  = (- 2± \sqrt{-32}) / 2)

  = (- 2 ± \sqrt{16(2)(-1)}) / 2

  = ( - 2 ± 4i\sqrt{2}) / 2

  = \frac{-2}{2} ± \frac{4i\sqrt{2} }{2}

  = - 1 ± 2i\sqrt{2} → D

Crank3 years ago
3 0

Answer:

Choice D is the answer.

Step-by-step explanation:

We have given a quadratic equation.

x²+2x+9 = 0

We have to find the solution of given equation.

From given equation, a = 1, b = 2 and c = 9.

x = (-b±√b²-4ac) / 2a is quadratic formula to find the solve quadratic equation.

Putting given values in formula, we have

x = (-2±√(2)²-4(1)(9) ) / 2(1)

x = (-2±√4-36) / 2

x = (-2±√-32) / 2

x = (-2±√16√-2 ) /2

x = (-2±4√2√-1) / 2                                 ∵ i = √-1

x = 2(-1±2√2i) / 2

x = -1±2√2i is the solution of given solution.

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Math PLEASE HELP IM SO CONFUSED IM ATTACHING THE SLIDES!!!!
slavikrds [6]

Answer:

  • x = 19, TS = 22

Step-by-step explanation:

  • Use ratios to solve for x. Corresponding sides have same ratio.

Q1

  • (x + 5)/30 = (36 - 20)/20
  • (x + 5)/30 = 16/20 = 4/5
  • 5(x + 5) = 4(30)
  • 5x + 25 = 120
  • 5x = 95
  • x = 19

Q2

  • (5x - 2)/(3x + 1) = 39/26
  • (5x - 2)/(3x + 1) = 3/2
  • 2(5x - 2) = 3(3x + 1)
  • 10x - 4 = 9x + 3
  • 10x - 9x = 3 + 4
  • x = 7

TS = 3x + 1 = 3(7) + 1 = 22

4 0
3 years ago
Pleaseeee tell me how you got the answer thank you
Sergio [31]
I did this! just think formulas!!!! :)
4 0
4 years ago
In 10 years, Roman will be 2 times Seth's age. 5 years ago Roman was 3 times Seth's age. HOW OLD IS SETH???
aalyn [17]
Let s be Seth's age. let r be Romans age. 5 years ago Seth was s-5 and Roman was three times as old, or 3(s-5), or 3s-15=r-5

in ten years Seth will be s+10 and Roman will be twice as old, or 2(s+10), or 2s+20=r+10
3s-15 =r-5
r=3s-10

2s+20=r+10
r=2s+10

3s-10=2s+10
s=20

Seth is 20 years old

setting the two equations equal gives us
3(s-5)=2(s+10)
3s-15=2s+20
s=35
5 0
3 years ago
2 (x + 3) - 1 = 3x + 5 - x
tekilochka [14]
All real numbers
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4 0
3 years ago
What does “period” do or mean when graphing a periodic function?
Anton [14]
Hello!

A period of a function like the sin graph or cosine graph are periodic because they repeat themselves on a interval and never end and each interval from trough to trough or peak to peak is called one period. Or another way if looking at it is one period is the time for one complete cycle of motion before it repeats itself.

Hope this helps thanks.
5 0
4 years ago
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