We have 4(k-6)-(3k+2)=-5 and the answer is k=21
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: (3,6)
Rewrite in vertex form and use this form to find the vertex (h,k)
T = 6 [h]
s = 340 [mi]
v=s/t=340/6=56.7 [mi/h]
Answer C.