# Thread: Need to find value for X

1. ## Need to find value for X

Can some one please let me know how the value for x is 2.13?

Thanks a lot.

2. ## Re: Need to find value for X

What have you tried? Have you learned to solve equations yet?

3. ## Re: Need to find value for X

Originally Posted by Siron
What have you tried? Have you learned to solve equations yet?
No I have not

4. ## Re: Need to find value for X

Originally Posted by thashrif

Can some one please let me know how the value for x is 2.13?

Thanks a lot.
Before I can proceed, I need to know if you meant to type (1 + x^2)/12 or
1 + (x^2/12) for the numerator part of the fraction.

5. ## Re: Need to find value for X

Originally Posted by mathland
Before I can proceed, I need to know if you meant to type (1 + x^2)/12 or
1 + (x^2/12) for the numerator part of the fraction.
Hi, Thank you very much for looking into this, the numerator part should be (1 + x^2)/12

Thanks a lot

6. ## Re: Need to find value for X

So the problem is to solve $\displaystyle 1.6911= 1.6242\frac{\frac{1+ x^2}{12}}{1.0062}$.

First do the arithmetic on the right:$\displaystyle \frac{1.6242}{12(1.0062)}= 0.134516$ to 6 decimal places. That means the equation is $\displaystyle 1.611= 0.134516(1+ x^2)$. Divide both sides by 0.134516: $\displaystyle 0.134516= x^2+ 1$.

Subtract 1 from both sides. $\displaystyle x^2= -0.8655$ which has no real number soltutions. if you are allowed complex numbers, the solution is plus or minus $\displaystyle \sqrt{0.8655}$ times i.

7. ## Re: Need to find value for X

Originally Posted by thashrif

Can some one please let me know how the value for x is 2.13?

Thanks a lot.
I worked this problem twice and did not come close to your answer for x.

You say that x = 2.13.

If x = 2.13, then after evaluation, we should get the same answer on both sides of the equation.

Let x = 2.13

1.6199 = 1.6242 [(1 + x^2)/12)] divided by 1.0062

1.6199 = 1.6242 [(1 + (2.13)^2)/12)] divided by 1.0062

1.6199 = 1.6242 [(1 + 4.5369)/12)] divided by 1.0062

1.6199 = 1.6242 [(5.5369)/12)] divided by 1.0062

As I continued to simplify, I did not get 1.6199 on both sides of the equation. So, the answer for x that you suggested (2.13) is not correct.
Find a calculator and continue simplifying where I ended my computation. I'm sure you will agree.

8. ## Re: Need to find value for X

Originally Posted by thashrif
No I have not
the equality is true.

9. ## Re: Need to find value for X

Originally Posted by HallsofIvy
That means the equation is $\displaystyle 1.611= 0.134516(1+ x^2)$. Divide both sides by 0.134516: $\displaystyle 0.134516= x^2+ 1$.
Mistake?

First it should be 1.6911 instead of 1.611.

Secondly,

$\displaystyle \frac{1.611}{0.134516}= 11.98 (2 d.p.)$

Correct me if I am wrong.

Originally Posted by thashrif
Hi, Thank you very much for looking into this, the numerator part should be (1 + x^2)/12

Thanks a lot
http://www.wolframalpha.com/input/?i=1.6199+%3D+1.6242*%28%281+%2B+x^2%29%2F%2812*1. 0062%29%29+find+x