Posted by anonymous on Thursday, September 9, 2010 at 3:25pm.
rationalise 5+2square root 5 divided by square root 5.
please can someone help me on how to get the answer 2+square root 5

maths  bobpursley, Thursday, September 9, 2010 at 3:39pm
(5+2sqrt5)/sqrt5 * (sqrt5/sqrt5)=
(2*sqrt5*sqrt5+5sqrt5)/(sqrt5*sqrt5)=
(2*5+5sqrt5)/5=2+sqrt5 
maths  anonymous, Thursday, September 9, 2010 at 3:58pm
but how do you get 2*5+5squared root 5 to become 2+sqrt5 ?