Step-by-step explanation:
step 1. wow! 670° I think you mean 67°
step 2. the 3 internal angles of a triangle add up to 180°. let x be the third angle
step 3. x + 102 + 67 = 180
step 4. x + 169 = 180
step 5. x = 11°.
Answer:
3x+39
a=8, b=0 and c=-6
see pic for expln
