Which classification best represents a triangle with side lengths 6 cm, 10 cm, and 12 cm?
1. acute, because 62 + 102 < 122
2.acute, because 6 + 10 > 12
3.obtuse, because 62 + 102 < 122
4.obtuse, because 6 + 10 > 12

The answer is 3.obtuse, because 62 + 102 < 122. If a^2 + b^2 > c^2, then the triangle is acute. If a^2 + b^2 = c^2, then the triangle is right. If a^2 + b^2 < c^2, then the triangle is obtuse. So, a = 6 cm, b = 10 cm, and c = 12 cm. Let's check if 6^2 + 10^2 is equal to 12^2. 6^2 + 10^2 = 12^2. 36 + 100 = 144. 136 < 144. Therefore, the triangle is obtuse.

The answer is C: Obtuse, because 6^2+10^2<12^2

When the coefficient of X is positive!