Geometry
Alternate Angles Worksheets
Find two missing alternate interior angles on marked parallel-line diagrams, with whole degrees, tenths or hundredths.
Preview and downloadGeometry practice
Find All Missing Angles Worksheets
Find seven missing angles from one given on parallel lines, or mix in right-angle split diagrams for complementary-angle reasoning.
Ready-made English PDF · fixed settings
Customization below makes a separate PDF.
Fixed English ready-made files. Custom settings below apply only to the configured PDF.
Ready to print
Start with a ready-made worksheet
Find every missing numbered angle using the marked parallel lines or right angles.
Download the practice pages alone, or include a separate answer key or teacher model. Longer activities may use more than one page.
Customize this worksheetBuild from the given angle
Use a direct vertical or corresponding equality, then use a straight-line supplement to reach the other measure class.
Learning objective
What this activity builds
Combine corresponding, alternate, vertical, supplementary and complementary relationships to find missing angles.
Worked example
One angle where a transversal crosses parallel lines is 63 degrees. Find its vertical angle and an adjacent angle.
63 degrees and 117 degrees.
Vertical angles are equal. Adjacent angles forming a straight line total 180 degrees, so 180 - 63 = 117. Corresponding positions at the other intersection repeat these measures.
Teaching notes
Make the practice count
- Begin with the given angle, then use equal or supplementary angles.
- Parallel-line diagrams have eight numbered angles and one given measure.
- Mixed mode adds two right-angle split diagrams: complementary parts add to 90 degrees.
Make it yours
Customize the practice
Choose your options, update the preview, then download the exact same pages.
Six numbered diagrams give one angle and ask for every other angle. Parallel Lines keeps the source-style set; Mixed adds two perpendicular right-angle split graphs.
Enlarged pages scroll. PDF size stays the same.
A useful next step
Related activities
Geometry
Corresponding Angles Worksheets
Use matching positions at parallel-line intersections to find missing corresponding angles, with three precision options.
Preview and download
Geometry
Complementary angles worksheets
Find one missing angle in 9, 12 or 15 complementary pairs using whole numbers, tenths or hundredths. Numbered diagrams show the two regions and a separate answer key preserves every given measure.
Preview and download