20.
N = (M + P)/2; P =(N + Q) /2 si N = 4P/5
suma masurilor unghiurilor unui patrulater convex = 360°
M + N + P + Q = 360
N = (M + P)/2; N = 4P/5⇒ (M + P)/2 = 4P/5⇒ M = 3P/5
P =(N + Q) /2 ⇒ 2P = N + Q ⇒2P = 4P/5 + Q⇒ Q = 6P/5
M + N + P + Q = 360 devine
3P/5+4P/5+P+6P/5 =360
18P = 360×5
P = 100°
N = 4P/5=400/5=80°
M = 3P/5=300/5=60°
Q = 6P/5=600/5=120°
verificare 80 +100 + 60 +120 +...=360
360 = 360 deci rezolvarea este corecta!!!!
