+0  
 
0
520
1
avatar

x-7sqrt(x)+10=0 . the solution set is/are x = ?. is there an extraneous solution? if so what is / are x=?

math algebra
Guest Aug 27, 2014

Best Answer 

 #1
avatar+93691 
+10

Mmm interesting

x-7sqrt(x)+10=0

Let y=sqrt(x) then we have

y^2-7y+10=0

(y-2)(y-5)=0

y=2 or 5

$$\\\sqrt x = 2 \;or\; 5\\
x=4 \;or \;25\\\\
check\; x=4\\
4-7*2+10=0 \;true\\
check x=25\\
25-35+10=0 \;true\\\\
So\; x=4\; or\; x=25$$

Melody  Aug 27, 2014
 #1
avatar+93691 
+10
Best Answer

Mmm interesting

x-7sqrt(x)+10=0

Let y=sqrt(x) then we have

y^2-7y+10=0

(y-2)(y-5)=0

y=2 or 5

$$\\\sqrt x = 2 \;or\; 5\\
x=4 \;or \;25\\\\
check\; x=4\\
4-7*2+10=0 \;true\\
check x=25\\
25-35+10=0 \;true\\\\
So\; x=4\; or\; x=25$$

Melody  Aug 27, 2014

28 Online Users

avatar
avatar
avatar

New Privacy Policy

We use cookies to personalise content and advertisements and to analyse access to our website. Furthermore, our partners for online advertising receive information about your use of our website.
For more information: our cookie policy and privacy policy.