Question

find j.
write your answer as a whole number or a decimal. do not round.
j = \boxed{} meters
submit
work it out

Explanation:

Step1: Identify similar triangles

Triangles \( \triangle EDC \) and \( \triangle BAC \) are similar (right angles, vertical angles at \( C \) are equal, so AA similarity).

Step2: Set up proportion

For similar triangles, \( \frac{EC}{BC}=\frac{DC}{AC} \). Given \( EC = 5 \), \( BC = 15 \), \( DC = 3 \), \( AC = j \). So \( \frac{5}{15}=\frac{3}{j} \).

Step3: Solve for \( j \)

Cross - multiply: \( 5j=15\times3 \). Then \( 5j = 45 \), divide both sides by 5: \( j=\frac{45}{5}=9 \).

Answer:

9