# Find to the nearest degree, the interior angles of the triangle having vertices A(1, 5) B(-1, 9) and C(-6, 2).?

• Find to the nearest degree, the interior angles of the triangle having vertices A(1, 5) B(-1, 9) and C(-6, 2).?  Answer #1 | 01/01 2014 17:47 here are the answers using the Cosine Law: b² = a² + c² - 2ac cos(B) sides (a,b,c): 8.6023, 7.6158, 4.4721 angles (A,B,C): 86.6335°, 62.1027°, 31.2637° is an acute scalene triangle
Positive: 100 %
Answer #2 | 31/12 2013 00:53 Slope is rise over run. Run is horizontal distance, left to right. Run is always positive because we always go left to right. Rise is the vertical change in that same distance. A negative rise means it drops. The slope is the tangent of the angle between the line and the x axis. A(1, 5) to B(-1, 9): This line runs 2 units from -1 to 1 and rises -4 units from 9 to 5 so the slope is -2. B(-1, 9) to C(-6, 2): This line runs 5 units from -6 to -1 and rises 7 units from 2 to 9 so the slope is 7/5. C(-6, 2) to A(1, 5): This line runs 7 units from -6 to 1 and rises 3 units from 2 to 5 so the slope is 3/7. Now you can find the included angles by simple arithmetic.
Positive: 66.666666666667 % 