# Math Help - can someone help please

1. ## can someone help please

My calulator is broken and I need this tomorrow. In triangle abc, a=7, b=9 and c=11. Find the three angle measures of the triangle. Using sin

2. Originally Posted by jwein4492
My calulator is broken and I need this tomorrow. In triangle abc, a=7, b=9 and c=11. Find the three angle measures of the triangle. Using sin
using sin what? you cannot use the law of sines here. and this is not a right triangle, so Pythagoras or trig ratios won't help us. use the law of cosines.

$a^2 = b^2 + c^2 - 2bc \cos A$

you can use that to find angle A. Similar formulas can get you angles B and C. Or, once you have angle A, you can use the law of Sines to get the other angles. Your choice