Well take the bottom and in this case its 18 and 30 so 18 x 30 = 540 then you do the two 15's times 30 and thats 450 times the 2 is 900 so 540+900+216 = so thats 1656 m 2 :)))))))))))
it would be that because if the graph is going to the left that means it is less than x and the opposite is for greater than. Now if there is a closed circle that means the sign is equal to hence the line under the sign. So therefore it's x≤-2