3. Eric is flying an airplane at an altitude of 2200 feet. He sees his house on 1 point the ground at a 45-degree angle of depression. What is Eric's horizontal
distance from his house at this point?
2200 ft
A. 110 feet
B. 220 feet
C. 1100 feet
D. 2200 feet

D    2200 feet

Step-by-step explanation:

Let d = the horizontal distance

tan 45 = 2200/d

dtan 45 = 2200

d = 2200/tan 45

d = 2200 ft.

Another solution is to recognize that the triangle is a 45-45-90 triangle and that the legs are congruent in the triangle.  So, the horizontal leg is the same as the vertical leg = 2200

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional