identifying congruent figures on a grid

Check the final answer first, then review the worked steps.

Problem

identifying congruent figures on a grid

Answer

Top-left: Yes, Top-right: No, Bottom-left: Yes, Bottom-right: No

Step-by-step solution

  1. Definition of Congruence: Two figures are congruent if they have the exact same shape and size. This means one figure can be mapped onto the other through rigid transformations (translation, rotation, or reflection).
  1. Analyze the first pair (top left): The two trapezoids have the same dimensions. Counting the grid units, both have a top base of 2 units, a bottom base of 4 units, and a height of 3 units. Since they are identical in size and shape, they are congruent. Answer: Yes.
  1. Analyze the second pair (top right): The two circles have different radii. The top circle has a diameter of 2 units, while the bottom circle has a diameter of 4 units. Because their sizes are different, they are not congruent. Answer: No.
  1. Analyze the third pair (bottom left): Both rectangles have a width of 2 units and a height of 4 units. Since they have the same dimensions, they are congruent. Answer: Yes.
  1. Analyze the fourth pair (bottom right): The first triangle is a right-angled triangle with base 3 and height 2. The second triangle is an isosceles triangle with base 4 and height 4. Since the shapes and sizes are different, they are not congruent. Answer: No.