Hey there!
It seems your problem is simply trying to rewrite the sentence.
Let's rewrite our sentence, from the phrase after the comma to the phrase before the comma.
Essentially, we are just flipping the sentence structure.
It should be this:
The two angles are complementary if the sum of the two angles are 90 degrees.
Let's take a good look at our answers.
A.) There are two angles.
While this is a true statement, it's a little too vague to understand. We can eliminate this answer choice.
B.) The sum of two angles is 90 degrees.
This is also a true statement, but it doesn't describe what type of angles sum to 90 degrees, so we can eliminate this as well.
C.) The angles are complementary.
This is similar to answer choice A. It's a little too vague for specific understanding. We can eliminate this answer choice.
D.) Angles are complementary if their sum is 90 degrees.
This is an accurate statement, and provides details to support it's claim, also rewriting the original sentences into one properly. This answer choice is correct.
Your answer is D.)
I hope this helps!
I wrote it out this time, so I didn't forget any work like last time. LOL
So, we start by solving what the numbers are..
2x10^5 = 200000 IN 2010!
Now this is where you might get confused, that WAS 2.5 times the number IN 1985
So you divide 200,000 by 2.5 = 80,000
Therefore its C.
The surface area of the square bottom = L x W = 7 x 7 = 49 cm^2
The area for one of the triangles = 1/2 x base x height = 1/2 x 7 x 9 = 31.5 cm^2
There are 4 triangles, the total area for the triangles = 31.5 x 4 = 126 cm^2
Total area = base + triangles = 49 + 126 = 175 cm^2
