SOLUTION: Tutor, I was hoping you could help me with this problem. I can not seem to get it to check out and I am not sure where I am making the mistake. Solve for X x^2 + 4x +

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Question 102876: Tutor,
I was hoping you could help me with this problem. I can not seem to get it to check out and I am not sure where I am making the mistake.
Solve for X
x^2 + 4x + 4 = 7
I know I have the factor the left-hand side but I must be doing something wrong because it is not working out for me. Any help would be great. Thank you in advance for your time.

Found 2 solutions by rapaljer, bucky:
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
The left side is a perfect square trinomial, which makes this work this way:
x%5E2+%2B+4x+%2B+4+=+7+
%28x%2B2%29%5E2+=+7

Next, take the square root of each side:
x%2B2=+0%2B-sqrt%287%29+

Finally, subtract 2 from each side:
x=-2%2B-sqrt%287%29+

R^3
Dr. Robert Rapalje, Retired

Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
If you factor the left side you get:
.
%28x+%2B+2%29%5E2+=+7
.
Then if you take the square root of both sides you get:
.
x+%2B+2+=+sqrt%287%29
.
Note the right side has a plus and minus sign. If you now subtract 2 from both sides
to get rid of the 2 on the left side you get:
.
x+=+-2+%2B-+sqrt%287%29
.
Hope this helps you to find the source of your difficulty.
.