Question

Solve ABC with B = 122°, b = 18 feet and c = 12 feet.

Answer 1

Answer:

C = 34 degrees, A=8.6 feet

Step-by-step explanation:

Use sine law:

$\frac{sin122}{18} = \frac{sinC}{12}$

$sin^{-1} [12(\frac{sin122}{18})]= C$

C = 34 degrees

Now that you have the C and B degrees, solve for A degrees

180 - 34 - 122 = 24 degrees for angle A

Same way as above use sine law to find the side for a now:

$\frac{18}{sin122} = \frac{A}{sin24}$

A=8.6 feet

** Thing to note is that you can rearrage the sine formula to have either the legnth or the angle on top. It's pretty straightforward, find the angles you do have and then work from there. If sine law doesnt work with your example, use cosine law. and work backwards. Wish you luck.