Check my solution to a radical equation

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Could a tutor check my solution to my radical question? It is enclosed in this attachment as a word document.
 
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Your attachment needs to be approved. Either way, it's still pretty dangerous to open word attachments.

Type it up and we'll take a look at it.
 
Why don't check your own answer? Just put your answer back into the original equation and do the arithmetic.
 
You can plug your answer back into the equation to see if it works out. Its absolutely correct & absolutely wrong all at the same time. Can you figure out why? Plug your values back in & see why I said what I said. Your first step contains an algebra error, also think factoring for the first step.
 
Is this correct?

3x + x*sqrt(5) = 2

solution

(3x + x*sqrt(5)) = 2

I factored out the x
x (3 + sqrt(5)) = 2

Divide both sides by sqrt(5) + 3
x (3 + sqrt(5) / (sqrt(5) + 3) = (2) / (sqrt(5) + 3)

cancel

x = (2) / (sqrt(5) + 3) final answer

Is this correct?
 
Last edited:
3x + x√5 = 2

²√5 = 5^½
3x + (5^½)x = 2
~5.24x=2
x=~0.38

i get the same
 
Last edited:
scientist said:
Is this correct?

3x + x*sqrt(5) = 2

solution

(3x + x*sqrt(5)) = 2

I factored out the x
x (3 + sqrt(5)) = 2

Divide both sides by sqrt(5) + 3
x (3 + sqrt(5) / (sqrt(5) + 3) = (2) / (sqrt(5) + 3)

cancel

x = (2) / (sqrt(5) + 3) final answer

Is this correct?
Yes, that is correct. You could make it look nicer by "rationalizing the denominator": multiply both numerator and denominator by [itex]\sqrt{5}- 3[/itex] and you get
[tex]x= \frac{2\sqrt{5}- 6}{2}= \sqrt{5}- 3[/itex]<br /> <br /> By the way, none of these are really "radical" equations since they don't involve roots of the <b>unknown</b> number. [itex]\sqrt{5}[/itex] is just another number!<br /> <br /> Oh, and there are no "tutors" here. Just us folks.[/tex]