The area of D is given by:

The average value of f over D is given by:
I hope this helps you
slope=y2-y1/x2-x1
slope=2-(-1)/1-2
slope=3/-1
slope= -3
f(x) being even means
f(x) = f(-x)
So the zeros come in positive and negative pairs. If there are an odd number of intercepts like there are here, it's because one of them is x=0 which is its own negation.
Given zero x=6 we know x=-6 is also a zero.
So we know three zeros, and know the other two zeros are a positive and negative pair.
The only choice with (-6,0) and (0,0) is A.
Choice A
Answer:
-2
Step-by-step explanation:
X1 Y1 X2 Y2
(-15, 30) (7, -14)
Y2-Y1 = -14-30 = -44 = -2
———————————————
X2-X1 = 7-(-15)= 22 = 1