I Find the measures of the unknown angles described in Problems 15 - 20. When appropriate, give answers to the nearest tenth. 15) If all three angles of a triangle are congruent, what is the measure of each angle? 60 16) If two angles of a right triangle are congruent, what are their measures? 90 17) A right triangle has one acute angle measuring 37. What does the other acute angle measure? 53 18) In a right triangle, if the measures of the other two angles are 2x - 4 and 3x + 10, what are the measures of these two angles? 3X+10=2X-4 2*-14-4=3*-14+10 3X-2X=-4-1 -28-4=-42+10 0 -32 AND -32 X=-14 19) A triangle has angles with measures 2x + 5, 2x - 10, and x + 15. Fin (2x+5)+(2x-10)+(x+15)=180 5/5x=170/5 2*34+5 9 .he measure of each angle. 5x+10=180 x=34 =73 =58 =83 5x=180-10 20) One angle of a triangle is three times as large as the second angle. The exterior angle at the third vertex is 100. Find the measures of all three interior angles. a+b+c=180 a+b=100 x+3x=100 4/4x=100/4 x=25