lucy5761 lucy5761
  • 03-10-2019
  • Mathematics
contestada

solve 3x^2=-12x-15
x=-4+2i
x=-4+i
x=-2+2i
x=-2+i

Respuesta :

zrh2sfo
zrh2sfo zrh2sfo
  • 03-10-2019

Answer:

x = -2 + i or x = -2 - i

Step-by-step explanation:

Solve for x:

3 x^2 = -12 x - 15

Add 12 x + 15 to both sides:

3 x^2 + 12 x + 15 = 0

Divide both sides by 3:

x^2 + 4 x + 5 = 0

Subtract 5 from both sides:

x^2 + 4 x = -5

Add 4 to both sides:

x^2 + 4 x + 4 = -1

Write the left hand side as a square:

(x + 2)^2 = -1

Take the square root of both sides:

x + 2 = i or x + 2 = -i

Subtract 2 from both sides:

x = -2 + i or x + 2 = -i

Subtract 2 from both sides:

Answer: x = -2 + i or x = -2 - i

Answer Link

Otras preguntas

Solve the equivalent ratio.Josie is training for a race. The ratio of the number minutes she runs to the number of miles she runs is 24 to 3. she plans to run 1
I need help is it a active scalene triangle yes or no?
In VWX the measure of
what is the value of cos^-1 (-0.26)?
is The Gobi Desert is Asia's largest desert
Columbus had a plan to find a new route to Asia, but something else happened. What went wrong with his plan?
Find the lengths of DE and EF. Note: Segments BC and DF are parallel. A) DE = 7 cm; EF = 5 cm B) DE = 10 cm; EF = 6 cm C) DE = 9 cm; EF = 15 cm D) DE = 19.6
what are the next three terms in the sequence 7/8, 1/2, 1/8
What is the main need or want the wave technology shown meets? A. To diagnose health problems more quickly B. To keep teeth clean and healthy more easily C. To
Why are landslides considered to be natural hazards?