Classify Figures by Lines and Angles - 4th Grade Math
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What is the measure of a right angle?
What is the measure of a right angle?
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A right angle measures $90^\circ$. It's one-fourth of a full rotation or a square corner.
A right angle measures $90^\circ$. It's one-fourth of a full rotation or a square corner.
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What does it mean for two lines in a plane to be parallel?
What does it mean for two lines in a plane to be parallel?
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Parallel lines never meet and stay the same distance apart. They maintain constant separation and extend infinitely without intersecting.
Parallel lines never meet and stay the same distance apart. They maintain constant separation and extend infinitely without intersecting.
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Identify the triangle type by angles: angles are $60^\circ$, $60^\circ$, and $60^\circ$.
Identify the triangle type by angles: angles are $60^\circ$, $60^\circ$, and $60^\circ$.
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Not a right triangle. All angles are less than $90^\circ$, so no right angle exists.
Not a right triangle. All angles are less than $90^\circ$, so no right angle exists.
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Identify the triangle type by angles: angles are $90^\circ$, $45^\circ$, and $45^\circ$.
Identify the triangle type by angles: angles are $90^\circ$, $45^\circ$, and $45^\circ$.
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Right triangle. Contains one $90^\circ$ angle, making it a right triangle.
Right triangle. Contains one $90^\circ$ angle, making it a right triangle.
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Identify the quadrilateral: it has $2$ pairs of parallel sides but no right angles.
Identify the quadrilateral: it has $2$ pairs of parallel sides but no right angles.
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Parallelogram (not a rectangle or square). Without right angles, it can't be a rectangle or square.
Parallelogram (not a rectangle or square). Without right angles, it can't be a rectangle or square.
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Which option describes a square: $2$ pairs parallel and $4$ right angles, or $1$ pair parallel and $0$ right angles?
Which option describes a square: $2$ pairs parallel and $4$ right angles, or $1$ pair parallel and $0$ right angles?
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$2$ pairs parallel and $4$ right angles. Squares are rectangles with all sides equal.
$2$ pairs parallel and $4$ right angles. Squares are rectangles with all sides equal.
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Identify the figure: a quadrilateral with exactly one pair of parallel sides.
Identify the figure: a quadrilateral with exactly one pair of parallel sides.
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Trapezoid. Only one pair of opposite sides are parallel.
Trapezoid. Only one pair of opposite sides are parallel.
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Which option must be true for a rectangle: parallel sides, perpendicular sides, or both?
Which option must be true for a rectangle: parallel sides, perpendicular sides, or both?
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Both: opposite sides are parallel and adjacent sides are perpendicular. Rectangles have both parallel opposite sides and $90^\circ$ corners.
Both: opposite sides are parallel and adjacent sides are perpendicular. Rectangles have both parallel opposite sides and $90^\circ$ corners.
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Which option must be true for a trapezoid: $0$, $1$, or $2$ pairs of parallel sides?
Which option must be true for a trapezoid: $0$, $1$, or $2$ pairs of parallel sides?
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Exactly $1$ pair of parallel sides. By definition, trapezoids have only one pair of parallel sides.
Exactly $1$ pair of parallel sides. By definition, trapezoids have only one pair of parallel sides.
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Identify the figure: a quadrilateral with $4$ equal sides and $4$ right angles.
Identify the figure: a quadrilateral with $4$ equal sides and $4$ right angles.
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Square. It's a special rectangle where all sides have equal length.
Square. It's a special rectangle where all sides have equal length.
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Identify whether the lines are parallel, perpendicular, or neither: one is horizontal, one is vertical.
Identify whether the lines are parallel, perpendicular, or neither: one is horizontal, one is vertical.
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Perpendicular. Horizontal and vertical lines meet at $90^\circ$.
Perpendicular. Horizontal and vertical lines meet at $90^\circ$.
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Identify whether the lines are parallel, perpendicular, or neither: two different horizontal lines.
Identify whether the lines are parallel, perpendicular, or neither: two different horizontal lines.
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Parallel. All horizontal lines are parallel to each other.
Parallel. All horizontal lines are parallel to each other.
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Choose the correct classification: a quadrilateral with $4$ right angles and only $1$ pair of parallel sides.
Choose the correct classification: a quadrilateral with $4$ right angles and only $1$ pair of parallel sides.
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Impossible (a quadrilateral with $4$ right angles has $2$ pairs of parallel sides). Four right angles force opposite sides to be parallel.
Impossible (a quadrilateral with $4$ right angles has $2$ pairs of parallel sides). Four right angles force opposite sides to be parallel.
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Identify the figure: a parallelogram with $4$ right angles.
Identify the figure: a parallelogram with $4$ right angles.
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Rectangle. It's a special parallelogram where all angles are $90^\circ$.
Rectangle. It's a special parallelogram where all angles are $90^\circ$.
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Identify the figure: a quadrilateral with $2$ pairs of parallel sides.
Identify the figure: a quadrilateral with $2$ pairs of parallel sides.
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Parallelogram. Both pairs of opposite sides are parallel to each other.
Parallelogram. Both pairs of opposite sides are parallel to each other.
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What is a right triangle?
What is a right triangle?
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A triangle with exactly one right angle of $90^\circ$. One of its three angles must be exactly $90^\circ$.
A triangle with exactly one right angle of $90^\circ$. One of its three angles must be exactly $90^\circ$.
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Which angle type has a measure greater than $90^\circ$ but less than $180^\circ$?
Which angle type has a measure greater than $90^\circ$ but less than $180^\circ$?
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Obtuse. Angles between $90^\circ$ and $180^\circ$ are classified as obtuse.
Obtuse. Angles between $90^\circ$ and $180^\circ$ are classified as obtuse.
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Which angle type has a measure less than $90^\circ$: acute, right, or obtuse?
Which angle type has a measure less than $90^\circ$: acute, right, or obtuse?
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Acute. Angles between $0^\circ$ and $90^\circ$ are classified as acute.
Acute. Angles between $0^\circ$ and $90^\circ$ are classified as acute.
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Which angle type has measure less than $90^\circ$?
Which angle type has measure less than $90^\circ$?
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An acute angle. It's smaller than a right angle, like a sharp corner.
An acute angle. It's smaller than a right angle, like a sharp corner.
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What is the definition of a rhombus using sides?
What is the definition of a rhombus using sides?
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A quadrilateral with $4$ equal side lengths. All sides have the same length, like a diamond shape.
A quadrilateral with $4$ equal side lengths. All sides have the same length, like a diamond shape.
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