It's a Quadratic equation and you can't solve it by factoring, gimme a sec.

Gah, it has to equal x? I can't do that.

It's a Quadratic equation and you can't solve it by factoring, gimme a sec.

 

 

Gah, it has to equal x? I can't do that.

Hint, assume that it equals zero.

4X² + 8X + 3 = 0

Oh, in that case, yes. Quadratic all the way. (I had no way of knowing what it equaled, lol)

Quadratic equation is: Negative B plus or minus the square root of B squared minus 4AC, divided by 2A.

-8 ± √( (8)² - 4(4)(3) )

----------------------------

2(4)

4*4*3 = 48. 8 squared is 64. 64-48 = 16, leaving

-8 ± √(16)

--------------

8

The square root of 16 is 4, leaving

-8 ± 4

----------

8

-8 + 4 is 4, divided by 8 is .5.

-8 - 4 = 12, divided by 8 is 1.5.

Am I close?

Oh, in that case, yes. Quadratic all the way. (I had no way of knowing what it equaled, lol)

 

Quadratic equation is: Negative B plus or minus the square root of B squared minus 4AC, divided by 2A.

 

-8 ± √( (8)² - 4(4)(3) )

----------------------------

2(4)

 

4*4*3 = 48. 8 squared is 64. 64-48 = 16, leaving

 

-8 ± √(16)

--------------

8

 

The square root of 16 is 4, leaving

 

-8 ± 4

----------

8

 

-8 + 4 is 4, divided by 8 is .5.

 

-8 - 4 = 12, divided by 8 is 1.5.

 

Am I close?

Close, except that -8 + 4 = -4, divided by 8 is -.5, and -8 - 4 = -12, divided by 8 = -1.5.

Other then that, it was right.

And I learned it this way:

4X² + 8X + 3 = 0 is:

(2X+1)(2X+3) = 0

(2X+1) = 0

X = -.5

(2X+3) = 0

X = -1.5

Then it's just a matter of checking the above equation with the two values of X.

This method is just FOIL factoring the equation, which takes some trial and error, I like the method you used, I can't quite describe it, I tried to, but I ended up not making any sense. =P