Explanation:
We are given two angles measures and one side. Notice the given angle and the side that is opposite to that given angle is given. We need to find side x. But can we also find the angle opposite of the side we are trying to find. Yes we can
Remeber that triangles interior angles add up to 180.
Remeber that triangles interior angles add up to 180.One angle measure 90 and the other measure is 57 so
![90 + 57 + x = 180](https://img.qammunity.org/2022/formulas/mathematics/high-school/9lep2xa3wagh4i3ibv3jaf8r2ky9jfe2op.png)
![x = 33](https://img.qammunity.org/2022/formulas/mathematics/high-school/co46tuq7mjcfnzdglgaw4tr9w70rc61l16.png)
So the angle opposite of the side we are trying to find is 33.
Since we know two angles and two sides that are opposite of those two angles respectively, we can use what is called Law of Sines
![(b)/( \sin(b) ) = (c)/( \sin(c) )](https://img.qammunity.org/2022/formulas/mathematics/high-school/9gelrfq74ru14keb5plvwzluzy8qoxqczr.png)
where the numerator are the side measures, and the denominator are the angle measures.
Plug in the respectively values. Angle 57 is opposite of 10 and Angle 33 is opposite of x.
![(10)/( \sin(57) ) = (x)/( \sin(33) )](https://img.qammunity.org/2022/formulas/mathematics/high-school/92233n6hx7qm0cv9czl2jyjkt180zgo8p5.png)
Multiply both sides by sin 33 to isolate x.
We get
![x = 6.494](https://img.qammunity.org/2022/formulas/mathematics/high-school/d04mdxfpityt3crpqx9cfvpstozbvp8eu1.png)
Round if needed
In other words, apply law of sines when you have two angles and two sides that are opposite of those angles respectively.