Grade 8 Geometry Practice — Easy

Question 1 of 37Score 0/0Easy

Question 1 of 37: Which transformation slides every point of a figure by the same distance in the same direction?

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Keep going: Read the lesson: Transformations: Translations, Rotations, Reflections & Dilations Angle Relationships Surface Area & Volume
Answer key for parents & teachers (37 questions)
  1. Which transformation slides every point of a figure by the same distance in the same direction? — Translation. A translation slides all points by the same vector (a, b), moving the figure without rotating or flipping it.
  2. Which transformation flips a figure over a line? — Reflection. A reflection flips a figure over a line (axis of reflection), creating a mirror image.
  3. Which transformation turns a figure around a fixed point? — Rotation. A rotation turns a figure by a given angle around a fixed center point.
  4. Which transformation changes the SIZE of a figure? — Dilation. A dilation scales a figure by a factor k. If k ≠ 1, the size changes (k > 1 enlarges, 0 < k < 1 shrinks).
  5. After a translation, the image is _____ to the original. — Congruent. Translations are rigid motions — they preserve all distances and angles. The image is congruent to the original.
  6. Point A is at (2, 5). After translating by (3, −1), where is A'? — (5, 4). (2+3, 5+(−1)) = (5, 4).
  7. Point (6, 0) is dilated by factor 1/2 about the origin. The image is at: — (3, 0). (1/2 × 6, 1/2 × 0) = (3, 0).
  8. How many degrees does a half-turn rotation equal? — 180°. A half-turn is 180°. A full turn is 360°.
  9. The Pythagorean Theorem states: — a² + b² = c². The Pythagorean Theorem: a² + b² = c², where c is the hypotenuse and a, b are the legs.
  10. In a right triangle, the hypotenuse is: — Opposite the right angle (longest side). The hypotenuse is always the longest side, opposite the right angle.
  11. A right triangle has legs of 3 and 4. What is the hypotenuse? — 5. 3² + 4² = 9 + 16 = 25. √25 = 5. Classic (3, 4, 5) Pythagorean triple.
  12. A right triangle has legs of 5 and 12. What is the hypotenuse? — 13. 5² + 12² = 25 + 144 = 169. √169 = 13. The (5, 12, 13) triple.
  13. A right triangle has hypotenuse 10 and one leg 6. Find the other leg. — 8. 6² + b² = 10² → 36 + b² = 100 → b² = 64 → b = 8.
  14. What is the distance between (0, 0) and (3, 4)? — 5. d = √(3² + 4²) = √25 = 5.
  15. What is the Pythagorean Theorem used to find? — Side lengths of a right triangle. The Pythagorean Theorem relates the three side lengths of a right triangle: a² + b² = c².
  16. Two triangles are SIMILAR if: — They have the same shape (equal angles and proportional sides). Similar triangles have the same shape: corresponding angles are equal and corresponding sides are proportional.
  17. The AA Criterion for similarity states: — Two pairs of equal angles. AA (Angle-Angle): if two pairs of angles are equal, the triangles are similar. The third angle is forced to match since all angles sum to 180°.
  18. Why does knowing only 2 angle pairs guarantee triangle similarity? — Two angles determine the third since all angles sum to 180°. Since triangle angles sum to 180°, knowing 2 angles determines the third. Two matching pairs guarantee all three match.
  19. Triangle ABC has angles 50°, 60°, 70°. Triangle DEF has angles 50°, 70°, 60°. Are they similar? — Yes — AA criterion satisfied (same angles). Both triangles have the same angle set {50°, 60°, 70°}. Two angle pairs match → AA criterion → similar.
  20. What notation is used to indicate similar triangles? — ∼. ∼ (tilde) means "similar." ≅ means congruent. Note the order matters: △ABC ∼ △DEF means A↔D, B↔E, C↔F.
  21. Two similar triangles have sides in ratio 2:3. If the smaller triangle has a side of 8, the corresponding side of the larger is: — 12. 8 × (3/2) = 12. Multiply by the ratio to find the corresponding side.
  22. To use AA similarity, you need: — 2 pairs of matching angles. AA requires exactly 2 pairs of equal angles (the third is determined automatically).
  23. An exterior angle of a triangle equals: — The sum of the two non-adjacent (remote) interior angles. Exterior Angle Theorem: the exterior angle equals the sum of the two remote (non-adjacent) interior angles.
  24. Two remote interior angles are 40° and 55°. What is the exterior angle? — 95°. Exterior angle = 40° + 55° = 95°.
  25. Two remote interior angles are 70° and 30°. What is the exterior angle? — 100°. Exterior angle = 70° + 30° = 100°.
  26. An exterior angle is 115° and one remote interior angle is 60°. What is the other remote interior angle? — 55°. 115° = 60° + x → x = 55°.
  27. An exterior angle is 130° and one remote interior angle is 70°. What is the other remote interior angle? — 60°. 130° = 70° + x → x = 60°.
  28. How does an exterior angle compare to each remote interior angle? — It is always larger than either one alone. The exterior angle equals the SUM of both remote angles, so it must be larger than either one individually.
  29. The exterior angle at a vertex plus the interior angle at the same vertex equals: — 180°. The exterior angle and interior angle at the same vertex form a straight line (linear pair) and sum to 180°.
  30. An exterior angle of 150° is created at one vertex. What is the interior angle at that same vertex? — 30°. Interior + exterior = 180°. Interior = 180° − 150° = 30°.
  31. The volume formula for a cylinder is: — V = πr²h. V_cylinder = πr²h. The base area is πr², multiplied by height h.
  32. The volume formula for a cone is: — V = (1/3)πr²h. V_cone = (1/3)πr²h. It is exactly one-third the volume of a cylinder with the same base and height.
  33. The volume formula for a sphere is: — V = (4/3)πr³. V_sphere = (4/3)πr³. Remember the 4/3 fraction and that the radius is CUBED.
  34. A cone's volume is what fraction of a cylinder with the same base and height? — 1/3. V_cone = (1/3)V_cylinder. Three cones fill exactly one cylinder.
  35. A cylinder has radius 3 cm and height 5 cm. What is its volume in terms of π? — 45π cm³. V = π(3²)(5) = π(9)(5) = 45π cm³.
  36. A sphere has radius 3. What is its volume in terms of π? — 36π. V = (4/3)π(3³) = (4/3)π(27) = 36π.
  37. What units are used for volume? — Cubic units (m³). Volume measures 3D space and is expressed in cubic units (m³, cm³, in³, ft³).