Hi Richard P
B = 47°
b = 9.15
c = 12.49
Draw your triangle so you can see the angles relative to the sides
The sum of the angles in a Triangle is 180 degrees so if you know the measure two angles you can use this information to calculate the measure of the missing angle B as follows:
180 -(46 + 87) = 180 - 133 = 47
B = 47°
Now you have the measures of all the angles in the triangle
If your drawing is correct (the sides are opposite the angles) you can use the Law of Sines to calculate the other two sides
You are given angle A and side a, the Law of Sines is below:
a/sinA = b/sinB = c/sinC
9/sin(46°) = b/sin(47°)
Cross multiply to solve for b
9sin(47°)/sin(46°) = 9.15
b = 9.15
You should repeat the process solve for side c.
Can you continue from here if not please just send a message and let me know if want further help?
Hope this helps.
