Posted by **Edwin** on Wednesday, February 2, 2011 at 9:19am.

3x^2-12x-24=0

- College Algebra -
**helper**, Wednesday, February 2, 2011 at 12:22pm
3x^2- 12x - 24 = 0

Solve the quadratic equation by completing the square:

Divide both sides by 3:

x^2 - 4x - 8 = 0

Add 8 to both sides:

x^2 - 4x = 8

Add 4 to both sides:

x^2 - 4x + 4 = 12

Factor the left hand side:

(x - 2)^2 = 12

Take the square root of both sides:

|x - 2| = 2 sqrt(3)

Eliminate the absolute value:

x - 2 = -2 sqrt(3) or x - 2 = 2 sqrt(3)

Add 2 to both sides:

x = 2 - 2 sqrt(3) or x - 2 = 2 sqrt(3)

Add 2 to both sides:

x = 2 - 2 sqrt(3) or x = 2 + 2 sqrt(3)

- College Algebra -
**sharlette**, Thursday, February 3, 2011 at 8:49am
A wheel made 672 revolutions at 35 1/5 revolutions per minute. How many minutes did it rotates?

## Answer this Question

## Related Questions

- algebra - 24x^4-12x^3+48x^2/-4x 24x^4-12x^3+12(-1) 24x^4-12x^3+(-12x) 2x^4-12x^3...
- algebra - 5x -3 = 11 + 12x combine like figures add 3 to both sides to remove ...
- Algebra - Can someone please check my work for me. Q: Plot the graph of the ...
- College algebra - 20x^2+12x
- College algebra - Find the value of f(x) = -3x^2 + 12x-8
- COLLEGE ALGEBRA ..HELP! - Solve by completing the square 12x^2+11x=5
- COLLEGE ALGEBRA - Solve by completing the square 12x^2+11x=5
- st paul (math college algebra) - rational expessions 7/3-8/12x-8
- college algebra - The average rate of change of g(x) = x3 - 12x + 16 from x = -2...
- algebra - (12x+1)(x-1)=-3 12x^+1=-3 12x^=-1-3 x=1/3 check this problem

More Related Questions