Answer: Choice B

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Explanation:
We'll be using the converse of the pythagorean theorem.
If we had a triangle with sides a,b,c and
was true, then we have a right triangle. Note: c is always the longest side
For the first answer choice we have: a = 5, b = 8, c = 12
Then,

which is false. This shows that we do not have a right triangle with sides 5,8,12. This rules out choice A. Choice C is a similar story.
Choice B on the other hand works because

We have a true statement at the end, which confirms <u>choice B</u> is a right triangle.
Answer:
35
Step-by-step explanation:
We have to solve the problems in the parenthesis first.
(16-2÷2)= (16-1)=(15)
20÷2-15÷3
(20÷2)-(15÷3)
10-5=5
50-5= 45
80-45= 35
Hope this helps!
Answer:
Below.
Step-by-step explanation:
Part A: 
Part B: Degree = 2, Classification = Quadratic
Part C: The polynomial is closed because it is multiplied. You CANNOT close under division.
Answer:
i'm not too good in this, but i believe the answer is -3
Step-by-step explanation:
the hcf, highest common factor, of both -3 and -15 is -3, hence making the answer -3? if this is incorrect, i apologize.
Part A:
-np - 70 < 40
+70
-np < 110
-n < 110/p
Part B
4w-7k=28
-7k=28-4w
7k=4w-28
k=4/7w-4