Rule: with any inscribed quadrilateral, the opposite angles are supplementary (they add to 180 degrees)
Based on that rule, we can say
d+100 = 180
d+100-100 = 180-100
d = 80
Answer: 80
C would be your answer and here is how you would solve the problem.
Y-int (0,4) because y=Mx+b, b is y-int
Slope is 2 means that the pattern of the graph is 2/1 up 2 over 1
Let x be the length of the garden
and y be the width of the garden.
since you only enclose 3 sides of the garden by a 40 ft fence. so the equation for this is:
2x + y = 40
and the area of the garden is 100 sq ft, so in equation
xy = 100
from equation 1, 2x + y = 40
y = 40 - 2x
substitute to equation 2
xy = 100
x ( 40 - 2x) = 100
40x - 2x^2 = 100
2x^2 - 40x + 100 = 0
x = 2.9 ft
y = 34.5 ft
