Question

which of the following statements is true? all rectangles are parallelograms. a trapezoid must have congruent sides. all rectangles are squares. every angle in a quadrilateral must be less than 180°. (additional text about progress bar omitted as irrelevant)

Explanation:

• Analyze Option 1: A parallelogram is a quadrilateral with two pairs of parallel sides. A rectangle has four right angles and also has two pairs of parallel sides (opposite sides are parallel and equal). So, by definition, all rectangles satisfy the properties of a parallelogram.
• Analyze Option 2: A trapezoid is defined as a quadrilateral with at least one pair of parallel sides. It does not require congruent sides. For example, a trapezoid with bases of length 3 and 5 and non - parallel sides of length 2 and 4 is a valid trapezoid without congruent sides.
• Analyze Option 3: A square is a special type of rectangle with all sides equal. But not all rectangles have all sides equal (a rectangle can have length and width of different measures). So, not all rectangles are squares.
• Analyze Option 4: In a concave quadrilateral, one of the interior angles is greater than \(180^{\circ}\). For example, a dart - shaped quadrilateral has an interior angle greater than \(180^{\circ}\). So, not every angle in a quadrilateral is less than \(180^{\circ}\).

Answer:

All rectangles are parallelograms.