Hello There!
.84 ÷ .02 ≈ 42
WORK SHOWN IN IMAGE ATTACHED
1 5/8
Trust me :)
If it's wrong then sue me instead :D
A(-5,5)
B(4,5)
C(2,0)
D(-5,-2)
AB,BC,CD,DA
AB = [4-(-5)),5-5]=[9,0]
Lenght

BC = [2-4,0-5]=[-2,-5]
Lenght

CD = [-5-2,-2-0]=[-7,-2]
Lenght

DA =[-5-(-5),-2-5]=[0,-7]
Lenght

sorted from longest to shortest:
AB, CD,DA,BC
As we see, the table shows 0 equals 4, so 4 is our y axis. we now know our equation is y=_x +4.
lets subtract and find the slope using

7-4 3
1-0 1 the slope is 3. lets substitute.
1(3)+4=7
the slope is 3.