The sides of a triangle measure 18 inches, 25 inches, and 36 inches. To the nearest degree, what is the measure of the largest angle?

AnimalMaster May 19, 2021

#1**+4 **

We use trig for this.

in triangle ABC:

the largest side is opposite the largest angle.

If we use the law of cosine, and instead of using finding c, we find gamma. we set c to the largest side so that we can find c's gamma.

we then solve:

\(36=\sqrt{18^2+25^2-2\cdot 18\cdot 25\cos \left(y\right)}\)

and we get:

y is about 112.67

BWStar May 19, 2021

#1**+4 **

Best Answer

We use trig for this.

in triangle ABC:

the largest side is opposite the largest angle.

If we use the law of cosine, and instead of using finding c, we find gamma. we set c to the largest side so that we can find c's gamma.

we then solve:

\(36=\sqrt{18^2+25^2-2\cdot 18\cdot 25\cos \left(y\right)}\)

and we get:

y is about 112.67

BWStar May 19, 2021