<span><span><span><span><span>(5)</span><span>(<span>−3</span>)</span></span>−<span><span>(4)</span><span>(<span>−3</span>)</span></span></span>−3</span>−<span><span>(3)</span><span>(<span>−3</span>)</span></span></span><span>=<span><span><span><span>−15</span>−<span><span>(4)</span><span>(<span>−3</span>)</span></span></span>−3</span>−<span><span>(3)</span><span>(<span>−3</span>)</span></span></span></span><span>=<span><span><span><span>−15</span>−<span>(<span>−12</span>)</span></span>−3</span>−<span><span>(3)</span><span>(<span>−3</span>)</span></span></span></span><span>=<span><span><span>−3</span>−3</span>−<span><span>(3)</span><span>(<span>−3</span>)</span></span></span></span><span>=<span><span>−6</span>−<span><span>(3)</span><span>(<span>−3</span>)</span></span></span></span><span>=<span><span>−6</span>−<span>(<span>−9</span>)</span></span></span><span>=<span>3</span></span>
Answer: AC=12 cm
Step-by-step explanation:
To solve this problem you must apply the law of sines, as you can see below:

Where:
a=13
A=85.2°
B=71.6°
Therefore, you must solve for b, then, you obtain that the lenght AC asked in the problem above is:

Https://us-static.z-dn.net/files/d4c/b1c4613c4e210c04f4bcda5810cab46d.png