r7ahMarityelilk r7ahMarityelilk 11-10-2016 Mathematics contestada If m∠4 = (3x)° and m∠8 = (x + 40)°, what is the measure of ∠4? ∠4 and ∠8 are vertical. A. 20˚ B. 60˚ C. 40˚ D. 120˚