Question

which proportion can be used to calculate the length of $overline{de}$?
a. $\frac{1.5}{de}=\frac{1.1}{7.2}$
b. $\frac{1.5}{de}=\frac{1.1}{3.3}$
c. $\frac{1.5}{de}=\frac{2.4}{3.3}$
d. $\frac{1.5}{de}=\frac{7.2}{1.5}$

Explanation:

Step1: Assume the triangles are similar.

Corresponding sides of similar triangles are proportional.

Step2: Match corresponding sides.

Side 1.5 mm in one triangle corresponds to side $DE$, and side 1.1 mm corresponds to side 3.3 mm. So the proportion is $\frac{1.5}{DE}=\frac{1.1}{3.3}$.

Answer:

B. $\frac{1.5}{DE}=\frac{1.1}{3.3}$