Let

using a graph tool
see the attached figure
The figure is a triangle
we know that
<u>The Heron's Formula</u> is a method for calculating the area of a triangle when you know the lengths of all three sides.
Hero's Formula is equal to

where
p is is half the perimeter of the triangle
a,b,c are the lengths of the sides of a triangle
so
Step 
<u>Find the length sides of the triangle</u>
a) <u>Find the distance AB</u>

Substitute


b) <u>Find the distance AC</u>

Substitute


c) <u>Find the distance BC</u>

Substitute


Step
<u>Find the perimeter of the triangle</u>

<u>Find the half of the perimeter </u>

Step 
<u>Find the area of the triangle</u>



therefore
<u>the answer is the option </u>
a) 1.65 mi^2.
Answer:
C. 1/3
Step-by-step explanation:
Answer:
so 5 miles upstream and 15 miles downstream
Step-by-step explanation:
25/5=5
30/2=15
Answer:
D
Step-by-step explanation:
70º
It's a supplementary angle so 180º - 110º