SOLUTION: Solve the equation √2x + 5 - √2x – 4 = 3 Help!!! Please expalin this!!

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Question 29890: Solve the equation
√2x + 5 - √2x – 4 = 3
Help!!! Please expalin this!!
Answer by Cintchr(481) About Me  (Show Source):
You can put this solution on YOUR website!
+sqrt%282x%2B5%29+-+sqrt%282x-4%29+=+3+ first you must add +sqrt+%282x-4%29+ to both sides.
+sqrt%282x%2B5%29+=+3+%2B+sqrt%282x-4%29+ Square both sides to get rid of the root on the left
+%28sqrt%282x%2B5%29%29%5E2+=+%283+%2B+sqrt%282x-4%29%29%5E2+ the root and the square on the left cancel each other out
+2x%2B5+=+%283+%2B+sqrt%282x-4%29%29%5E2+ FOIL the right side
+%283+%2B+sqrt%282x-4%29%29%283+%2B+sqrt%282x-4%29%29+
F: +3+%2A+3+=+9+
O: +3+%2A+sqrt%282x-4%29+=+3sqrt%282x-4%29+
I: +3+%2A+sqrt%282x-4%29+=+3sqrt%282x-4%29+
L: +sqrt%282x-4%29+%2A+sqrt%282x-4%29+=+2x+-+4+This is the right side of the equation.
+2x%2B5+=+9+%2B+3sqrt%282x-4%29+%2B+3sqrt%282x-4%29+%2B+2x+-+4+ Combine terms
+2x%2B5+=+5+%2B+2x+%2B+6sqrt%282x-4%29+ subtrace 2x and 5 from both sides to isolate the root.
+0+=+6sqrt%282x-4%29+ divide both sides by 6
+0+=+sqrt%282x-4%29+ square both sides to get rid of the radicand
+0%5E2+=+%28sqrt%282x-4%29%29%5E2+
+0+=+2x-4+ add 4 to both sides
+4+=+2x+ divide by 2 on both sides
+2+=+x+
CHECK YOUR SOLUTION
+sqrt%282x%2B5%29+-+sqrt%282x-4%29+=+3+ plug 2 in for x
+sqrt%282%282%29%2B5%29+-+sqrt%282%282%29-4%29+=+3+
+sqrt%284%2B5%29+-+sqrt%284-4%29+=+3+
+sqrt%289%29+-+sqrt%280%29+=+3+ root of 9 (assuming only positive roots) is 3, root of 0 is 0
+3+-+0+=+3+
+3+=+3+ YES!!