Fullstop 04.11.2012 13:16 Click to reveal hidden text $ r^2-6r+5=0 $ $ r^2-6r+5+4=4 $ $ r^2-6r+9=4 $ $ (r-3)^2=4 $ Therefore $ (r-3)^2 = 4 $.
fire123 04.11.2012 21:50 Another way to do this problem: r^2-6r+5=0 (r-5)(r-1)=0 r=5 r=1 (r-3)^2= (5-3)^2=4 or (r-3)^2=(1-3)^2=4