+0  
 
+1
39
2
avatar+153 

Solve \(x - 2 = \sqrt{9x - 36}\)

 Apr 19, 2020
 #1
avatar+20812 
+1

x - 2  =  sqrt(9x - 36)

square both sides:

(x - 2)2  =  ( sqrt(9x - 36) )2

x2 - 4x + 4  =  9x - 36

x2 - 13x + 40  =  0

(x - 5)(x - 8)

Possible answers:  5,  8

You should test both of these answers to see if both of them work.

 Apr 19, 2020
 #2
avatar+9447 
+1

Solve   \(x - 2 = \sqrt{9x - 36} \)

 

Hello bigmac!

 

\(x - 2 = \sqrt{9x - 36} \)               | square

\(x^2-4x+4= 9x - 36 \)      | bring it to zero format

\(x^2-13x+40=0\)

\(x=6.5\pm\sqrt{6.5^2-40}\\ x=6.5\pm 1.5\)        | p / q formula \(x=-\frac{p}{2}\pm\sqrt{(\frac{p}{2})^2-q}\)

\(x_1=8\\ x_2=5\)

laugh  !

 Apr 19, 2020
edited by asinus  Apr 19, 2020
edited by asinus  Apr 19, 2020

41 Online Users

avatar
avatar