Suppose a triangle has sides a, b, and c, and that a2 + b2

Question

Suppose a triangle has sides a, b, and c, and that a2 + b2 < c2. Let  be the measure of the angle opposite the side of length c. Which of the following must be true? Check all that apply.

 		A.	 is an acute angle.
 		B.	The triangle is a right triangle.
 		C.	cos < 0
 		D.	The triangle is not a right triangle.

mathstudent55 · Answer

Some info is missing.
What is the measure of the angle opposite the side of length c?
In A. What is an acute angle?
In C. cos of what?

tigerlover · Answer

hold on

tigerlover · Answer

$$con \theta < 0$$

tigerlover · Answer

$$\theta is an \acute \angle$$

mathstudent55 · Answer

I'm sure you  know the Pythagorean theorem and its famous equation:

$a^2 + b^2 = c^2$

mathstudent55 · Answer

Here you have $a^2 + b^2 < c^2$.

Is this triangle a right triangle?

tigerlover · Answer

it doesnt give a picture

tigerlover · Answer

its just the question and answer

mathstudent55 · Answer

The Pythagorean theorem states that if you have a right triangle with legs a and b, and hypotenuse c, then the equation below is true.

$a^2 + b^2 = c^2$

Also, the converse of the Pythagorean theorem is true. 
In other words, if you have a triangle with side lengths a, b, and c, and the equation

$a^2 + b^2 = c^2 $

is true, then the triangle is a right triangle.

mathstudent55 · Answer

You are given the inequality

$a^2 + b^2 < c^2$

Can this triangle be a right triangle?

tigerlover · Answer

yes?

mathstudent55 · Answer

The problem clearly states that for this triangle a^2 + b^2 < c^2
In a right triangle a^2 + b^2 = c^2 must be true.

Can a^2 + b^2 = c^2 and a^2 + b^2 < c^2 be both true at the same time?

tigerlover · Answer

i figuered it out.

mathstudent55 · Answer

Which choices did you choose?