The problem is asking to determine which sentence best describes a method for finding the area of the given polygon.

Observation:

The polygon is irregular but resembles a trapezoid. To calculate its area using the grid:

• One logical method is to subtract a smaller shape (like a triangle or rectangle) from a larger enclosing shape.

Answer Analysis:

1. Find the sum of the areas of two parallelograms:
   This does not apply to the given shape.

2. Find the sum of the areas of a parallelogram and a rectangle:
   This method does not fit the given figure.

3. Find the area of a square and then subtract the area of a triangle:
   This method is plausible. The enclosing square could be identified, and the triangle in the top-left corner could be subtracted.

4. Find the area of a square and then subtract the area of a rectangle:
   This does not fit, as the top-left subtraction involves a triangle, not a rectangle.

Correct Answer:

Find the area of a square and then subtract the area of a triangle.

Would you like further details about how to calculate this area step by step?

Related Questions:

1. How do you calculate the area of a square on a grid?
2. What is the formula for the area of a triangle?
3. How can subtraction of areas be applied to find irregular polygon areas?
4. What shapes other than triangles can be subtracted to simplify irregular polygons?
5. How does using grids help in determining areas accurately?

Tip:

When solving geometry problems with grids, count the squares carefully and verify if the shapes fit exactly within them!