DAY 15: The measures of the angles in a certain triangle are in the ratio 1: 5: 6. Find the measure of the smallest angle.
x +5x +6x=180
12x =180
x=15º
DAY 16: In triangle ABC, the measure of angle A = 7x - 32, the measure of angle B = 3x + 4, and the exterior angle at C has measure 12 (x - 5). Find the value of x.
exterior angle = sum of two remote (other) interiors
7x -32 +3x+4 =12(x-5)
10x -28 =12x -60
32-2x
x=16
DAY 17: Find the slope of the line perpendicular to the line through the points (21, 11) and (-4, -12).
11 - -12 / 21 - -4 =23/25
slope of perpendicular line is negative reciprocal =
-25/23 ( no 17!)
DAY 18: In a certain triangle, the largest angle is 6 times the smallest. The third angle is 18 less than 4 times the smallest. What is the measure of the smallest angle?
x= smallest
6x =largest
third angle =4x-18
x+6x +4x-18 =180
11x =198
x=18º