Answer:
Assume ΔABC is an acute triangle.
Step-by-step explanation:
Given the triangle ABC.
We have to tell the first step of indirect proving ΔABC is not an acute triangle.
An indirect proof, also known a proof by contradiction. When we use indirect proof method, we assume the opposite of our theory to be true and then by applying our assumed theory we contradict the given statement which proves our supposition is wrong. In other words, we assume our theory is false.
Hence, our first step is to
Assume ΔABC is an acute triangle.
Third option is correct.
Answer:
C
Step-by-step explanation:
So first, you find the area of a rectangle, which would be 15 * 30 = 450. Next, find the area of the semicircle by doing 
(you have to divide by 2 because it's only have a circle).
The radius is half of 15, so 15 / 2 = 7.5. This would be:
The last step is to add 450 + 88.3125 = about 538.3 m^2
