A Rectangle.
You are a square
You are a square or a rectangle
a square
A rhombus.
triangle
A square and a rectangle have diagonals of equal lengths
A Rectangle.
Not normally but in the shape of an isosceles trapezium they are equal
You are a square
rhombus
You are a square or a rectangle
a square
Any rectangle will have diagonals that are equal. Don't forget that since squares are also a special type of rectangle that they would also have congruent diagonals as well.
A rectangle
a pentagon
A rhombus.