find the perimeter of an isosceles triangle with side lengths of 5+x, 5+x, and xy. Write in simplest form.

perimeter = 10+2x+xy

To get the perimeter, you add up all the outer sides

side1+side2+side3 = (5+x)+(5+x)+(xy) = 10+2x+xy

The like terms 5 and 5 add to 10. The other pair of like terms x and x add to 2x. There isn't anything to pair with xy, so we leave it as is.

Best answer that i found on yahoo ok   set :   x= length of 2nd piece in cm  x- 3= length of 1st piece in cm  x-4= length of 3rd piece in cm  then since you know they all came from the 20 cm ribbon you add them together and set them equal to 20x+ x-3 +x-4 = 20  3x - 7= 20  3x= 27  x= 9  the shortest piece is the third piece which is x- 4  x-4  9-4 = 5  the length of the smallest piece is 5 cm.  the other lengths are  9 cm  6 cm