Answer:
DEC+DEF=180
DEC=180-116
DEC=64°
in triangle DCE
angle D+angle C+angle E=180
7y+6+4y+64=180
11y+70=180
11y=180-70
11y=110
y=110/11
y=10°
angle C=4y
=4(10)
=40°
45 and 16 because:45 - 16 = 29
1/2-1/3
(1/2)x3-(1/3)x2
3/6-2/6
1/6
Ok so what's the question