Unlock harder levels by getting an average of 80% or higher.

Earn up to 5 stars for each level
The more questions you answer correctly, the more stars you'll unlock!

Each game has 10 questions.
Green box means correct.
Yellow box means incorrect.

Unlock harder levels by getting an average of 80% or higher.

Earn up to 5 stars for each level
The more questions you answer correctly, the more stars you'll unlock!

Each game has 10 questions.
Green box means correct.
Yellow box means incorrect.

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Math Games for Teachers

VIII - Geometry

Standard 8.G.1.1 - Use the fact that the angle sum of triangles is 180º and quadrilaterals is 360º to find the missing interior angle.

Included Skills:

Understanding shapes:
• Properties of quadrilaterals ‐ Sum of angles of a quadrilateral is equal to 360° (By verification)
• Properties of parallelogram (By verification)
- Opposite sides of a parallelogram are equal,
- Opposite angles of a parallelogram are equal,
- Diagonals of a parallelogram bisect each other. [Why (iv), (v) and (vi) follow from (ii)]
- Diagonals of a rectangle are equal and bisect each other.
- Diagonals of a rhombus bisect each other at right angles.
- Diagonals of a square are equal and bisect each other at right angles.

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