can someone check my work?
solve √(2x-1)=x-8
i came up with x=13 x=5. may i ask which one it is ?

Question

can someone check my work? 
solve √(2x-1)=x-8
i came up with x=13 x=5. may i ask which one it is ?

hartnn · Answer

if you put back x=5
you'll get $\sqrt{9} =-3 $
which isn't true...its just +3 and not -3

hartnn · Answer

x=13 is correct.

hartnn · Answer

the reason you got 2 values instead of one is that you might have squared both sides of that equation. this adds/attaches one more root to the equation which may not satisfy the original equation.

anonymous · Answer

oooh. thanks :) i understand now. i did square both sides because i did not understand which property to do..

hartnn · Answer

ok, welcome ^_^
glad i could help :)