Solve: (3k + 11)^2 = 7
here's what I have so fare, please check and/or correct:
(3k + 11)(3k + 11) = 7
9k^2 + 33k + 33k + 121 = 7
9k^2 + 66k = 7 - 121
9k^2 + 66k = -1124

Question

Solve: (3k + 11)^2 = 7
here's what I have so fare, please check and/or correct:
(3k + 11)(3k + 11) = 7
9k^2 + 33k + 33k + 121 = 7
9k^2 + 66k = 7 - 121
9k^2 + 66k = -1124

mertsj · Answer

Just leave it in its original form and take the square root of both sides.

anonymous · Answer

You subtracted wrong. 7 - 121 = -114... Then get it back to the other side and factor. All numbers are divisible by 3 so start there

anonymous · Answer

Answers are -4.548584 and -2.78475

anonymous · Answer

okay so answer the first respons i would : the squareroot of 3k + 11 = the square root of 7?

mertsj · Answer

Yes.  Now you're on the right track.  Just remember that there are 2 square roots of 7...the positive one and the negative one.

mertsj · Answer

I should look like this:
$$3k+11=\pm \sqrt{7}$$

mertsj · Answer

Now subtract 11 from both sides:

anonymous · Answer

divide by 3 on both sides?

mertsj · Answer

$$3k=-11\pm \sqrt{7}$$

mertsj · Answer

Now divide by 3.  yes.

anonymous · Answer

so the answer is k = -11 +- the square root of 7/ 3

mertsj · Answer

yes

mertsj · Answer

$$k=\frac{-11\pm \sqrt{7}}{3}$$

anonymous · Answer

okay cool thank u

mertsj · Answer

yw