Answer:
a=38.21321°
b=14.61693
Step-by-step explanation:
Use cosine rule (c²=a²+b²-2abcosy), where y is the angle, c is the side opposite the angle and a and b are the other two sides.
c²=a²+b²-2abcosy
5²=7²+3²-2(7)(3)cosa
25=49+9-42cosa
42cosa=33
cosa=0.78571428571
a=38.21321°
c²=a²+b²-2abcosy
b=√(15²+9²-2(15)(9)cos70)
b=14.61693
