Question

Which classification best represents a triangle with side lengths 10 in., 12 in., and 15 in.? acute, because 102+122>152 acute, because 122+152>102 obtuse, because 102+122>152 obtuse, because 122+152>102

Answer 1

a is the best option because the sum of any two sides of a triangle is greater than the third sid . HOPE IT HELPS YOU ^-^ .

Answer 2

Answer:

The correct option is acute, because  $10^{2}+12^{2}=244>15^{2}$

Step-by-step explanation:

Using cosine law,

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

If $a^{2}+b^{2}=c^{2}$ then triangle will be right angled

 $a^{2}+b^{2}> c^{2}$ then $\theta$ will be acute

 $a^{2}+b^{2}<c^{2}$  then $\theta$ will be obtuse

Here, $10^{2}+12^{2}=244>15^{2}$

⇒Option A will be correct