posted by JEFF BOMB .
the diagonals of an isosceles trapezoid are each 17,the altitude is 8,and the upper base is 9.Find the perimrter of the trapezoid.
Hint: If the diagonals are equal, then it must be an isosceles trapezoid.
Construct altitudes from the ends of the side of 9 units
You should be able to see right-angled triangles with hypotenuse of 17
(you should get a length of 21 for the other base and 10 for the length of the other two sides.)