Rebecca has a triangular piece of board. She cut it along a line parallel to the base of the triangle as shown below.

What is the length of the line along which she cut the board?

5 inches

8 inches

11 inches

6 inches

Question

Rebecca has a triangular piece of board. She cut it along a line parallel to the base of the triangle as shown below.   
  
 
  
What is the length of the line along which she cut the board?

 5 inches

 8 inches

 11 inches

 6 inches

anonymous · Answer

attachment

jim_thompson5910 · Answer

The triangles are similar, so they form a proportion 


3/(3+5) = x/16


where x is the unknown length


Solve this equation for x to find your answer.

anonymous · Answer

is it 11 inches?!

jim_thompson5910 · Answer

no, you should have


3/(3+5) = x/16

3/8 = x/16

3*16 = 8x

48 = 8x

48/8 = x

6 = x

x = 6