3r+n2−r+5−2n+2<span />=3r+n2+−r+5+−2n+2=3r+n2+−r+5+−2n+2<span />=(n2)+(−2n)+(3r+−r)+(5+2)<span />=n2+−2n+2r+7<span /><span />
=n2−2n+2r+7
2/9×5=10/45
3/5×9=27/45
so 3/5 is bigger then 2/9
5/7×5=25/35
3/5×7=21/35
So 5/7 is larger than 3/5
So from least to greatest the numbers are
2/9 then 3/5 then 5/7
So your answer is A
subsitute x = 6 into the lengths
3(6) -7
18 - 7
11cm
(6) + 5
11cm
therefore it is a square when x = 6 because the sides are all equal