Question

which equation represents the model? 61 + x = 21; 21 + 4x = 61; 21 + x = 61; 61 + 4x = 21; model image with 21, x, x, x, x segments summing to 61

Explanation:

Step1: Analyze the model

The model has a segment of length 21 and four segments each of length \( x \), and the total length is 61. So the sum of 21 and \( 4x \) should equal 61.

Step2: Match with equations

Looking at the options, the equation \( 21 + 4x = 61 \) represents this relationship.

Answer:

\( 21 + 4x = 61 \) (the second option in the top row of the equation choices)