this geometry question

First  one

Orginal  perimeter  =  2 ( 12 + 17)

New perimeter  =  2 ( 12*12 + 12*17)  =   2 ( 12 (12 + 17) )  =  12 * 2 (12 + 17)

So....the perimeter is increased by a factor of 12

Second one

hypotenuse  = sqrt  ( leg1 ^2  +  leg2 ^2 )  =

sqrt  (15^2  + 25^2 )  =

sqrt  ( 225  + 625)    =

sqrt ( 850)  =  29.15 ft