(-22, 302.5) Question 2
7.15 pts
Sandra was comparing the electricity of two different companies. One company is charging $49 per month and $0.10 per kilowatt used.
The other company wanted $39 per month, but will charge $0.15 for all kilowatts after the first 100 kilowatts. Sandra used the following
system of equations to represent the situation.
Ca = 49 + 0.102
Cb = 39 +0.15(
2100)
Which answer is a reasonable solution, and what does it represent?

there are lots of ways.   pick's theorem tells us if the vertices are lattice points the area a is

a = b/2 + i - 1

where b is the number of boundary lattice points and i is the number of interior lattice points.

in the figure i count b=16, i=50 so

a = 8 + 50 - 1 = 57

let's try the shoelace formula.   the area is half the sum of the cross products of the sides.  

a(-2,6)   -2(2)-6(-5) = 26

b(-5,2)   -5(-3) - 2(-2) = 19

c(-2,-3) -2(-3) - (-3)(4) = 18

d(4,-3)   4(3) - (-3)(5) = 27

e(5,3)   5(3) - 3(1) = 12

f(1,3)     1(6) - 3(-2) = 12

a(-2,6)

each of the cross products is twice the area of the triangle with the associated side and one vertex the origin. so the area of abo=26/2=13.

area = (1/2) (26 + 19 +   18 + 27 + 12 + 12) = 57

that checks!

i think 1: 2

step-by-step explanation:

2nd one in the first row is correct