SOLUTION: can someone help me solve for x please? x^2+4x+4=7

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Question 79377: can someone help me solve for x please?
x^2+4x+4=7
Found 2 solutions by jim_thompson5910, Edwin McCravy:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2%2B4x%2B4=7
x%5E2%2B4x-3=0 Subtract 7 from both sides
Now use the quadratic formula to solve for x
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B4x%2B-3+=+0) has the following solutons:

x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%284%29%5E2-4%2A1%2A-3=28.

Discriminant d=28 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-4%2B-sqrt%28+28+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%284%29%2Bsqrt%28+28+%29%29%2F2%5C1+=+0.645751311064591
x%5B2%5D+=+%28-%284%29-sqrt%28+28+%29%29%2F2%5C1+=+-4.64575131106459

Quadratic expression 1x%5E2%2B4x%2B-3 can be factored:
1x%5E2%2B4x%2B-3+=+1%28x-0.645751311064591%29%2A%28x--4.64575131106459%29
Again, the answer is: 0.645751311064591, -4.64575131106459. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B4%2Ax%2B-3+%29


So the solution is:
x=-4.64575131106459 or x=0.645751311064591

Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!

Can someone help me solve for x please? 


         x² + 4x + 4 = 7


                   

Get 0 on the right by subtracting 7 from both sides


           x² + 4x - 3 = 0

Use the quadratic formula:
                  ______ 
            -b ± Öb²-4ac
        x = —————————————
                2a 

where a = 1; b = 4; c = -3

                     _____________
             -(4) ± Ö(4)²-4(1)(-3)
        x = ————————————————————————
                     2(1) 
                   _____ 
             -4 ± Ö16+12
        x = —————————————
                  2

                   __ 
             -4 ± Ö28
        x = ———————————
                 2 

                   ___ 
             -4 ± Ö4·7
        x = ———————————
                 2 

                    _ 
             -4 ± 2Ö4
        x = ———————————
                 2 

                      _
             -4     2Ö7
        x = ———— ± ——————
              2       2
                  _
        x = -2 ± Ö7 
                       _
Using the +, x = -2 + Ö7, which
is one solution and equals about .6457513111
                       _ 
Using the -, x = -2 - Ö7, which
is the other solution and equals about -4.645751311


Edwin