Answer:
a)
x/5=3
Multiply both sides by 5
5*x/5=3*5
The 5’s on the left side cancel out so your left with...
x=15
b)
x/2=8.5
Multiply both sides by 2
2*x/2=8.5*2
The 2’s on the left side cancel out so your left with...
x=17
P.S * represents multiplication