You have to use ur ruler so u can see what the longest side is, So basically use the ruler and look up the centimetre mark and then it shows you what number is at and whatever the biggest number is is what the longest side is.
You would have to make 465=1550-7 1/2 x and find x Subtract 1550 from both sides -1085=-7 1/2x Divide -7 1/2 on both sides And the answer is 144 2/3 Sorry about ur bad luck