Page 165 - ArithBook5thEd ~ BCC

Solution. △ABC ∼△ADE because DE ∥ BC. Corresponding sides are proportional, hence

AC 2ft. + 2 ft. 4 in. BC BC
= = = .
AE 2ft. DE 2ft. 6in.

Converting all measurements to inches, and letting x represent the length of BC in inches,

52 x
=
24 30
which gives x =65 inches, or 5 ft. 5 in.

5.5.1 Exercises
In the first two exercises, the triangles are similar, and similarly marked angles are equal. Find the length
x in each case.
4.5
1.

1.6 1 3
x

1.5

A E 3 D
2.

1.5 1

x

B C
1.4

F

Page 165