Find an integer, x, such that 5, 10, and x represent the lengths of the sides of an obtuse triangle.
A. 4
B. 5
C. 6
D. 11

Question

Find an integer, x, such that 5, 10, and x represent the lengths of the sides of an obtuse triangle.
A. 4
B. 5
C. 6
D. 11

anonymous · Answer

does your problem specify which will be which side?

directrix · Answer

Use this theorem:

If a, b, and c represent the lengths of the sides of a triangle, and c is the longest length, then the triangle is obtuse if c^2 > a^2 + b^2.

anonymous · Answer

well the only way that could possibly work out, or at least as far as i can tell, is that 10 is the longest side, which would mean that alll a, b,and c would work

directrix · Answer

@dave0116
@MLeighW 

Here's why I think option A of 4 will not work.

That would give the sides as 4, 5, and 10.

Recall the Triangle Inequality Theorem which states that one side of a triangle is shorter than the sum of the lengths of the other two sides.

10 is not less than (4+5). No triangle with sides 4, 5, and 10 exists.

anonymous · Answer

haha well it seems that you know more about this than me, i am only recalling my knowledge of triangles, i will bow out now since i am obviously of no help hahaha