Geometry Lessons for Grade 7
Use scale drawings, construct triangles, apply angle relationships, and solve problems involving circle measurements, area, surface area, and volume. These lessons give each idea room for an interactive diagram, worked examples, and hands-on exploration.
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Reflex Angle
A reflex angle measures more than 180 degrees and less than 360 degrees.
Open lesson →Full Rotation
A full rotation measures 360 degrees.
Open lesson →Adjacent Angles
Adjacent angles share a common vertex and side without overlapping interiors.
Open lesson →Complementary Angles
Complementary angles add to 90 degrees.
Open lesson →Supplementary Angles
Supplementary angles add to 180 degrees.
Open lesson →Linear Pair
A linear pair is a pair of adjacent supplementary angles.
Open lesson →Vertical Angles
Vertical angles are opposite angles formed by two intersecting lines.
Open lesson →Transversal Line
A transversal is a line that intersects two or more lines.
Open lesson →Corresponding Angles
Corresponding angles are in matching positions when a transversal crosses lines.
Open lesson →Alternate Interior Angles
Alternate interior angles lie between the lines on opposite sides of the transversal.
Open lesson →Alternate Exterior Angles
Alternate exterior angles lie outside the lines on opposite sides of the transversal.
Open lesson →Hypotenuse & Legs
In a right triangle, the hypotenuse is opposite the right angle and the other sides are the legs.
Open lesson →Triangle Inequality
The sum of any two side lengths in a triangle must be greater than the third side.
Open lesson →Exterior Angle Theorem
A triangle's exterior angle equals the sum of the two remote interior angles.
Open lesson →Interior Angle Sum
The interior angle sum of an n-gon is (n minus 2) times 180 degrees.
Open lesson →Exterior Angle Sum
The exterior angles of a polygon always add to 360 degrees.
Open lesson →Circumference
The circumference is the distance around the circle.
Open lesson →Chord
A chord is a segment with both endpoints on the circle.
Open lesson →Arc
An arc is a portion of a circle's circumference.
Open lesson →Sector
A sector is the region bounded by two radii and the included arc.
Open lesson →Lateral Area
Lateral area is the surface area of a solid excluding its bases.
Open lesson →Slant Height
Slant height is the distance measured along the side of a cone or pyramid.
Open lesson →Cross Sections
A cross section is the 2D shape formed when a solid is sliced by a plane.
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