sum of all sides of triangle=180°
7x+13x+16x=180°
36x=180°
x=180°/36
x=5
angle D=7x
=7(5)
D=35°
angle E=13(x)
=13(5)
E=65°
angle F=16x
=16(5)
F=80°
angle D=35°
angle E=65°
angle F=80°
Sin51=y/12
y=12sin51 units
y≈9.33 units (to nearest hundredth of a unit)
...
tanα=12/5
α=arctan2.4°
α≈67.38° (to nearest hundredth of a degree)
...
tan13=x/24
x=24tan13 units
x≈5.54 units (to nearest hundredth of a unit)
...
sin20=10/x
x=10/sin20 units
x≈29.24 units (to nearest hundredth of a unit)
1. added four to both sides
2. divided both sides by two
