To determine which model represents an algebraic expression equivalent to the original model, let's analyze the components given in the first model:
- 1 Rectangle labeled x: This represents +x.
- 3 Rectangles labeled negative x: This represents -3x.
- 3 Squares labeled 1: This represents +3.
- 2 Squares labeled negative 1: This represents -2.
Now, we can combine these components into an algebraic expression:
\[ x - 3x + 3 - 2 \]
This simplifies to:
\[ -2x + 1 \]
Now we need to evaluate the choices based on what they represent to see which one simplifies to \(-2x + 1\).
-
2 rectangles, each labeled negative x, and 1 square labeled 1
- This represents: \[ -2x + 1 \] (This matches.)
-
1 rectangle labeled x, 1 rectangle labeled negative x, 2 squares, each labeled 1, and 2 squares, each labeled negative 1
- This represents: \[ x - x + 2 - 2 = 0 \] (This does not match.)
-
3 rectangles, each labeled negative x, and 2 squares, each labeled negative 1
- This represents: \[ -3x - 2 \] (This does not match.)
-
1 rectangle labeled x and 3 squares, each labeled 1
- This represents: \[ x + 3 \] (This does not match.)
The correct response, which is equivalent to the original expression, is:
2 rectangles, each labeled negative x, and 1 square labeled 1 (equivalent to \(-2x + 1\)).