For this case we have that by definition, the equation of a line in the slope-intersection form is:

Where:
m: It is the slope
b: It is the cut point with the y axis
The slope is: 
Thus, the equation is of the form:

We substitute the given point and find "b":

Finally, the equation is:

Answer:

BCD should have to equal 24 degrees because angles ACB and BCD look Complimentary and a complimentary is 2 angles that equal 90 degrees when combined since ACB and BCD look like a 90 degree angle I would say that BCD is 24 degrees
area of shaded figure = l x w = 24 *18 = 432
area of white square = 12*12 = 144
area of shaded part = 432-144 = 288 m^2
Answer is A
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