Question

finding missing lengths of a scale drawing
determining a scale factor
how would a scale factor of 4 be used to determine the
lengths of the scale figure?
the scale factor is multiplied by
the original length.
the scale factor is added to the
original length.
the scale factor is subtracted
from the original length.
the scale factor is divided by the
original length.

Explanation:

Step1: Recall the formula for scale factor

The formula for scale factor \(k\) in the context of scale drawing is \(k=\frac{\text{scale length}}{\text{original length}}\). If we want to find the scale length \(L_s\) given the original length \(L_o\) and scale factor \(k\), we can rewrite the formula as \(L_s = k\times L_o\).

Step2: Analyze the options

• Option "The scale factor is added to the original length": This is incorrect. Addition is not the operation related to scale - factor in scale - drawing length calculation.
• Option "The scale factor is subtracted from the original length": This is incorrect. Subtraction is not the operation related to scale - factor in scale - drawing length calculation.
• Option "The scale factor is divided by the original length": This gives \(\frac{k}{L_o}\), which is not the formula for scale length.
• Option "The scale factor is multiplied by the original length": Using the formula \(L_s=k\times L_o\), if \(k = 4\) (the given scale factor), to find the scale - drawing length, we multiply the original length by the scale factor.

Answer:

The scale factor is multiplied by the original length.