First use Pythagoras theorem to find the remaining length of the base.
Then multiply the base with the altitude and divide that by 2 and you'll get the area
Answer:
-157.87
Step-by-step explanation:
1) the rules are:
and

2) according to the rules above:

The equation would be b = -a or a = -b
I hope this helps :)
The correct answer for this question is A.