In scientific notation the answer is: 0.00018 x 10^6
the 3rd vertex is on the x axis line which means Y =0
since the longer leg is twice as long as the shorter leg and the length of the shorter leg is a, then twice the length would be 2a ( 2 times a)
so the 3rd vertex is (2a,0)
Answer:
20 mm
Step-by-step explanation:

You posted the question twice ... I have repeated the answer here .. .
Find the area of all the sides:
10 x 9 = 90
9 x 8 = 72
1/2 x 6 x 8 = 24
1/2 x 6 x 8 = 24
6 x 9 = 54
Add them up:
90 + 72 + 24 + 24 + 54 = 264 square metres