Chapter 6.9, Problem 22STP

To determine

To find: The length of missing height of larger triangle.

Answer to Problem 22STP

Street sign is 3.15 meter tall.

Explanation of Solution

Given information: 

Two similar right triangles are given so that the height of the larger triangle, represents the height of street sign.

Concept used:

In similar triangles, the ratio of corresponding sides is equal always. So, in said given similar triangles,

  $\frac{\text{Height of larger triangle}}{\text{Height of smaller triangle}}=\frac{\text{Base of larger triangle}}{\text{Base of smaller triangle}}$

Calculation:

Based on above ratio set, on plug in all related value in it,

  $\frac{x}{0.35}=\frac{1.8}{0.2}$

On cross multiply,

  $x=\frac{1.8\times 0.35}{0.2}=9\times 0.35=3.15$

Based on above concept, the street sign is 3.15 m high.