Question

Help! Will medal and fan! please helpp
Suppose a triangle has sides a, b and c, and that a^2+b^2 10 years ago

Answer 1

1. (theta) is an obtuse triangle.
2. The triangle is not a right triangle.
3. The triangle is a right triangle.
4. cos(theta) < 0

Answer 2

@TrojanPoem Could you help on this one, too?

Answer 3

\[\cos \theta = \frac{ a^2 + b^2 - c^2 }{ 2ab }\]

a^2 + b^2 - c^2 < 0

costheta * 2ab = a^2 + b^2 - c^2

2abcostheta < 0 ( b, a are postive so we won't flip the sign)

costheta < 0

Answer 4

Okay I see. So answer 4 for sure

Answer 5

Answer 2, as well?

Answer 6

the triangle is obtuse too, as a^2 + b^2 < c^2

Notice that :

a2 + b2 > c2 (acute)

a2 + b2 = c2 ( right)

a2 + b2 < c2 ( obtuse)

Answer 7

Okay, awesome! Thanks so much for helping me again!

Answer 8

Any time.

Answer 9

The triangle isn't a right triangle as it's obtuse.