SOLUTION: Hey if any one knows how this is done school doesn’t provide the proper explanation {{{x=2sqrt(2x+5)}}}

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Question 1153074: Hey if any one knows how this is done school doesn’t provide the proper explanation x=2sqrt%282x%2B5%29
Found 2 solutions by ikleyn, MathLover1:
Answer by ikleyn(52795) About Me  (Show Source):
You can put this solution on YOUR website!
.

Your first step is to square both sides.



Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
x=2sqrt%282x%2B5%29........first square both sides to get rid of sqrt
x%5E2=2%5E2%2A%282x%2B5%29
x%5E2=4%282x%2B5%29
x%5E2=8x%2B20
x%5E2-8x-20=0.....factor completely: write -8x as -2x%2B10x
x%5E2-2x%2B10x-20=0.......group
%28x%5E2-2x%29%2B%2810x-20%29=0
x%28x-2%29%2B10%28x-2%29=0
%28x+-+10%29%28x+%2B+2%29+=+0
solutions:
if %28x+-+10%29+=+0=>x=10
if %28x+%2B+2%29+=+0=>x=-2

since you need solution that will make x=2sqrt%282x%2B5%29 true, check the solutions by plugging them into x=2sqrt%282x%2B5%29

x=2sqrt%282x%2B5%29=>x=10
10=2sqrt%282%2A10%2B5%29
10=2sqrt%2825%29
10=2%2A5
10=10=>true

x=2sqrt%282x%2B5%29=>x=-2
-2=2sqrt%282%2A%28-2%29%2B5%29
-2=2sqrt%28-4%2B5%29
-2=2sqrt%281%29
-2=2%2A1
-2=2=>false

=> solution to x=2sqrt%282x%2B5%29 is x=10