Which shapes are quadrilaterals? 1. Scalene right triangle
2. Obtuse scalene triangle
3. Isosceles right triangle
4. Hexagon
5. Pentagon
6. Right trapezoid
7. Venn diagram

Hey there! I'm happy to help!

A quadrilateral is any polygon (enclosed shape) with four sides. Let's see what each of these shapes are.

Scalene right triangle - the prefix tri- means three  (tricycle, tripod, triple, etc.), and all triangles have three sides, so this is not a quadrilateral.Obtuse scalene triangle - once again a triangle, so not a quadrilateral.Isosceles right triangle - would you look at that, another triangle! Not a quadrilateral.Hexagon - a hexagon is a six-sided polygon (hex=six), so this is not a quadrilateral.Pentagon - a pentagon is a five-sided polygon (pent=five, like Pentatonix!). Not a quadrilateralRight trapezoid - a trapezoid is a quadrilateral with at least one pair of parallel sides!Venn diagram - a Venn diagram is a compare and contrast chart made of two overlapping circles (ZERO sides), so this is not a quadrilateral.

So, the only shape on your list that is a quadrilateral is 6. right trapezoid.

Have a wonderful day! :D