Question

model:
-5 3x + 5
3x + 10 3x

Explanation:

Step1: Identify the terms

The blue rectangles represent \( x \) and the light blue represent \( 1 \), red rectangles with \(-x\) and dark red with \(-1\)? Wait, no, looking at the model: Let's count the \( x \)-terms (blue tall) and constant terms (light blue small and red small). Wait, maybe the first part is a visual for combining like terms. Wait, the options are constants or linear expressions. Wait, maybe the model is showing combining \( x \) and constant terms. Wait, let's re-express: Suppose the blue tall is \( x \), light blue small is \( 1 \), red tall is \(-x\)? No, maybe the first set (top) is \( x, 1, -x, -1 \), but the model below: Let's count the number of \( x \) (blue tall) and constants (light blue small and red small). Wait, in the model, how many \( x \) terms? Let's see: first row of model: two blue tall (\( x \))? Wait, no, the first blue tall is \( x \), then another blue tall? Wait, maybe the model is combining like terms. Wait, the original top has \( x, 1, -x, -1 \), but the model below: Let's count the \( x \) terms (blue tall) and constant terms (light blue small and red small). Wait, maybe the correct approach is to simplify the expression represented by the tiles. Let's assume that blue tall is \( x \), light blue small is \( 1 \), red tall is \(-x\)? No, maybe the red small is \(-1\). Wait, the options include \( 3x \), so maybe the \( x \) terms: let's see, if we have three \( x \) terms? Wait, no, maybe the model is showing \( 3x \) (three blue tall) and no constant terms? Wait, the options are \(-5\), \(3x +5\), \(3x +10\), \(3x\). Wait, maybe the tiles: blue tall is \( x \), light blue small is \( 1 \), red small is \(-1\). Wait, let's count the number of \( x \) (blue tall) and constants (light blue and red). Wait, in the model, how many blue tall (\( x \))? Let's see: first row of model: two blue tall? No, maybe the first blue tall is \( x \), then another blue tall, then a third? Wait, maybe the correct answer is \( 3x \), because if we combine like terms, the constants cancel? Wait, no, the original top has \( x +1 -x -1 = 0 \), but the model below: maybe the model is showing three \( x \) terms with no constants? Wait, the options include \( 3x \), so let's check: if the model has three \( x \) terms (blue tall) and no constant terms (since the constants cancel out), then the simplified expression is \( 3x \). Wait, but let's re-express: suppose the tiles are \( x, x, x \) (three blue tall) and constants that cancel. So combining like terms, the constants (1 and -1, etc.) cancel, leaving \( 3x \). So the answer is \( 3x \).

Wait, maybe the first part (top) is a visual for \( x +1 -x -1 \), but the model below is a different set? No, maybe the question is to simplify the expression represented by the tiles, and the result is \( 3x \). So the correct option is \( 3x \).

Step2: Match with options

The options are \(-5\), \(3x +5\), \(3x +10\), \(3x\). So the one with only \( 3x \) is the answer.

Answer:

\( 3x \) (the option D, assuming D is \( 3x \); but in the options given, the last one is \( 3x \), so the answer is the option with \( 3x \), i.e., the last option: \( 3x \))