SOLUTION: What is x? square root of (2-x) = x+4

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Question 703407: What is x?
square root of (2-x) = x+4
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

sqrt%282-x%29+=+x%2B4.......square both sides

%28sqrt%282-x%29%29%5E2+=+%28x%2B4%29%5E2
2-x=+x%5E2%2B8x%2B16
0=+x%5E2%2B8x%2Bx%2B16-2
+x%5E2%2B9x%2B14=0......use quadratic formula to find solutions

x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ ..a=1, b=9 and c=14

x+=+%28-9+%2B-+sqrt%28+9%5E2-4%2A1%2A14+%29%29%2F%282%2A1%29+

x+=+%28-9+%2B-+sqrt%28+81-56+%29%29%2F2+

x+=+%28-9+%2B-+sqrt%28+25+%29%29%2F2+

x+=+%28-9+%2B-+5+%29%2F2+

solutions:

x+=+%28-9+%2B5+%29%2F2+
x+=+-4%2F2+
x+=+-2+
or
x+=+%28-9+-5+%29%2F2+
x+=+-14%2F2+
x+=+-7+

+graph%28600%2C+600%2C+-10%2C+10%2C+-10%2C+20%2C+x%5E2%2B9x%2B14%29+