+0  
 
0
896
1
avatar+140 

i need to solve 

sqrt(3x-5)=x-2  i got these steps

3x-5=(x-2)(x-2)

3x-5=x^2-4x+4

0=x^2-x+9

a=1 b=-1 c=9

then simplified to

x=(1+sqrt(-35))/2

and i am stuck here on how to simplify further

 May 19, 2016
edited by Guest  May 19, 2016
 #1
avatar+129852 
0

Let's go from this step :

 

3x-5=x^2-4x+4        subtract 3x  from both sides and add 5 to both sides

 

0  = x^2 -7x + 9       this will not factor........using the quadratic formula, the two solutions are :

 

[ 7 + √13] / 2     = about   5.3028    or

 

[ 7 - √13] / 2     = about   1.6792

 

The second solution is extraneous, since it makes the right side of the original equation negative......and we can't ever get a negative answer from a positive root......this solution results from the squaring of both sides   [which often happens in these types of problems].....so.....

 

Only the first solution is "good"

 

 

cool cool cool

 May 19, 2016

1 Online Users