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vivalakoda
 2 years ago
Solve for x?
vivalakoda
 2 years ago
Solve for x?

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vivalakoda
 2 years ago
Best ResponseYou've already chosen the best response.0\[4\sqrt{x+9}=20 \]

vivalakoda
 2 years ago
Best ResponseYou've already chosen the best response.0I know how to solve is, I'm just not sure how to get rid of the 4 in the front of the radical.

Ladyalice25
 2 years ago
Best ResponseYou've already chosen the best response.0you need to remove the square from x+9 the way you do that is by squaring both side and you end up with x+9=(20/4)^2. then solve from there.

Ladyalice25
 2 years ago
Best ResponseYou've already chosen the best response.0x+9=20/4)^2. 20/4^2 = 25 then take 25 subtract 9. you will get the answer of x=34

dpaInc
 2 years ago
Best ResponseYou've already chosen the best response.2it's easy to see that this has NO SOLUTION: (4)*(5) = 20 so that means: \(\large 4\sqrt{x+9}=20 \rightarrow \sqrt{x+9}=5\) \(\large \sqrt{x+9}=5\) which has no solution because the left side is always positive but the right side is negative

vivalakoda
 2 years ago
Best ResponseYou've already chosen the best response.0Can't you just square both sides to get rid of the square root, then solve like an equation?

dpaInc
 2 years ago
Best ResponseYou've already chosen the best response.2yes you can try to do that... it's one technique you should try to solve it. but why continue when you know this is an impossible equation to solve?

dpaInc
 2 years ago
Best ResponseYou've already chosen the best response.2not impossible, no solution... if you do solve it, the solution is an extraneous solution....

vivalakoda
 2 years ago
Best ResponseYou've already chosen the best response.0If according to your answer it is √x+9 = 5 then you'd square both sides to have: x+9 = 25 subtract 9 from both sides and get 16 as x?

AntarAzri
 2 years ago
Best ResponseYou've already chosen the best response.0Difficult equation in history

dpaInc
 2 years ago
Best ResponseYou've already chosen the best response.2squaring both sides you get positive 25

vivalakoda
 2 years ago
Best ResponseYou've already chosen the best response.0Oh, that's right thanks so then x+9=25 subtract 9 then positive 16?

dpaInc
 2 years ago
Best ResponseYou've already chosen the best response.2yes... now let's see if the solution of x=16 works....

dpaInc
 2 years ago
Best ResponseYou've already chosen the best response.2\(\large (4)(\sqrt{x+9})=20 \) \(\large (4)(\sqrt{\color {red}{16}+9})=20 \) \(\large (4)(\sqrt{\color {red}{25}})=20 \) \(\large 4 \cdot 5 = 20 \) \(\large 20=20 \) ???? not a true statement

dpaInc
 2 years ago
Best ResponseYou've already chosen the best response.2so the solution of x=16 is extraneous and not really a solution.

AntarAzri
 2 years ago
Best ResponseYou've already chosen the best response.0solution \[\left 4 \right\]

dpaInc
 2 years ago
Best ResponseYou've already chosen the best response.2@AntarAzri , what's the solution?

AntarAzri
 2 years ago
Best ResponseYou've already chosen the best response.0\[\left 4 \right\]

dpaInc
 2 years ago
Best ResponseYou've already chosen the best response.2\(\large (4)(\sqrt{x+9})=20 \) \(\large (4)(\sqrt{4+9})=20 \) \(\large (4)(\sqrt{4+9})=20 \) \(\large (4)(\sqrt{13})=20 \) x=4 doesn't seem to work. That's not a solution.

vivalakoda
 2 years ago
Best ResponseYou've already chosen the best response.0my oh my I have headaches because of this problem..

AntarAzri
 2 years ago
Best ResponseYou've already chosen the best response.0no no i dont mean the x −4=4

dpaInc
 2 years ago
Best ResponseYou've already chosen the best response.2ok. whatever... my answer stands... NO SOLUTION to the equation: \(\large (4)(\sqrt{x+9})=20 \) \)

AntarAzri
 2 years ago
Best ResponseYou've already chosen the best response.0\[(\left 4 \right)(\sqrt{16+9})=20\]

dpaInc
 2 years ago
Best ResponseYou've already chosen the best response.2here's wolframs answer: http://www.wolframalpha.com/input/?i=solve+4*sqrt%28x%2B9%29%3D20

AntarAzri
 2 years ago
Best ResponseYou've already chosen the best response.0http://www.wolframalpha.com/input/?i=solve+ %E2%88%924*sqrt%28x%2B9%29%3D20

dpaInc
 2 years ago
Best ResponseYou've already chosen the best response.2if u don't understand my answer and expanation maybe someone else can give u a better answer... i will not argue my point further....

AntarAzri
 2 years ago
Best ResponseYou've already chosen the best response.0Do we agree that it can not be the root of a negative number gives a positive number ?

vivalakoda
 2 years ago
Best ResponseYou've already chosen the best response.0I'll see what my teacher says when she grades it. Thanks for your time
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