Core Connections Integrated II, 2015
CC
Core Connections Integrated II, 2015 View details
2. Section 6.2
Continue to next subchapter

Exercise 73 Page 347

Reflect one of the lines in the vertical segment that represents the street and draw a new segment from the reflected point to the opening of the opposite building.

About 36.4 feet below the art museum.
Diagram:

Practice makes perfect

To find the shortest combined distance, we first have to reflect one of the lines in the vertical segment that represents the street.

Next, we will draw a segment from the reflected point to the opening of the library.

If we examine the diagram, we see two right triangles. Note the angles at the point where the triangles meet form vertical angles. These angles are congruent by the Vertical Angles Congruence Theorem.

Since the triangles have at least two pairs of congruent angles, we know they are similar by the AA Similarity condition. The sides labeled x and 80-x are both the included side to the marked angles in the triangles. Therefore, they are corresponding legs. Using the triangles' similarity, we can write an equation containing x. 80-x/x=60/50 Let's solve this equation for x.
80-x/x=60/50
Solve for x
80-x=60/50* x
50(80-x)=60x
4000-50x=60x
4000=110x
110x=4000
x=36.36363...
x≈ 36.4
She should park about 36.4 feet below the art museum. Let's show this in a table. |c|c|c| x & 80-x & sum of hypotenuses 35.6 & 44.4 & 136.0203 36 & 44 & 136.0159 36.4 & 43.6 & 136.0147 36.8 & 43.2 & 136.0165 As you can see, the sum of the hypotenuses is minimized when x=36.4.