k
are we solving for x here?
\[\sqrt{x+7}-x=1\]Right?
x will = 9
It says solve and to check for extraneous solutions. And yes @SolomonZelman
\[\sqrt{x+7}-x=1\]\[\sqrt{x+7}-x\color{red} { +x }=1\color{red} { +x }\]\[\sqrt{x+7}=x+1\]square both sides\[(~\sqrt{x+7}~)\color{red} { ^2 }=(~x+1~) \color{red} { ^2 }\]\[x+7=x^2+2x+1\]so far so good?
Ahh okay. I'm following.
\[x+7\color{red} { -x }=x^2+2x+1\color{red} { -x }\]\[7=x^2+2x+1\]\[7\color{red} { -7 }=x^2+2x+1\color{red} { -7 }\]\[x^2+2x-6=0\]what about now?
Yes. It's a lot of steps, but it's helping me understand it better. What next??
can you do it now?
Well I'm not too sure. I had a few guesses what x was, but I don't think they're right. What would I do next? Sorry, I'm not too good at math.
Do we factor?
Sorry for not replying right away.
It's okay. Gave me time to look into the problem more. :)
\[\huge\color{blue}{ \frac{-b±\sqrt{b^2+4ac} }{2a} } \]
\[\huge\color{blue}{ \huge\color{red}{1}x^2+\huge\color{red}{2}x+\huge\color{red}{6}=0 } \]see the a b c ? plug them into the quadratic formula.
\[-1 \pm \sqrt{-1 + 4*2*6} / 2*2\]
Like that?
Not exactly....
Then how would I do it??
Sorry your equation was\[x^2+2x-6=0\] \[\huge\color{red}{ \frac{-2±\sqrt{ 1^2-4 \times 2 \times (-6)} }{2 \times 2} }\]
\[\huge\color{red}{ \frac{-2±\sqrt{49}}{4} }\]
\[\huge\color{red}{ \frac{-2±7}{4} }\]you tell me what the answers are....
@SolomonZelman those are what I got. Seems odd though.
Well, it's right though....
Really? Haha alright then. Thanks a bunch!
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