SOLUTION: Can someone help me solve this for X sqrtx+7 = x+1
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Question 35509
:
Can someone help me solve this for X
sqrtx+7 = x+1
Found 2 solutions by
Nate, rapaljer
:
Answer by
Nate(3500)
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(x+7)^(1/2)=(x+1)
(x+7)=(x+1)^2
x+7=x^2+2x+1
x^2+x-6=0
(x+3)(x-2)=0
x=-3 and x=2
If you plug in the -3, you get 2=-2 .... so -3 isn't an answer.
However, 2 is a right answer, so the answer is x=2.
Answer by
rapaljer(4671)
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put this solution on YOUR website!
Square both sides, which eliminates the radical on the left side:
This is quadratic, so set it equal to zero by subtracting x and 7 from each side.
It factors!!! (I think they ALWAYS do!!)
HOWEVER, you must check these answers, since you squared both sides of the equation. Substitute both values back into the original equation.
Check x = -3:
This answer must be rejected by the principle value definition of square root.
Check x = 2:
This answer checks!!
Final answer is x= 2.
R^2 at SCC