Question

What are the two cases in which the Laws of Cosines can be applied to solve a non-right triangle?
Case I. You know the measures of two angles and any side of the triangle.
Case II. You know the measures of two sides and an angle opposite one of the two known sides.
Case III. You know the measures of two sides and the included angle.
Case IV. You know the measures of all three sides.
answers :
A. Case I and Case III
B. Case II and Case IV
C. Case III and Case IV
D. Case I and Case II

Answer 1

its C ?

Answer 2

you are correct

In case III you can use the law of cosines to find the third missing side, then you can find the other two angles

similarly, the law of cosines applies to case IV because you can solve for each angle one at a time to fully solve the triangle

Answer 3

yayy ! (: thanks for checking

Answer 4

case II will deal with the law of sines (although it's never a guaranteed triangle), so that eliminates all the other choices

you're welcome