## Trigonometry (10th Edition)

$65^{\circ}; 115^{\circ}$
1. Supplementary angles have a sum of 180 degrees $(3x+5) +5x+15) =180$ 2. Solve for x : $8x+20=180$ $8x=160$ $x=20$ 3. Replace x to find the angles: $5(20)+15=115 ^{\circ}$ $3(20)+5=65 ^{\circ}$