Question 253285
Why do we need three equations? We need three equations because we will have three unknowns. We need one equation for each unknown.
Let the digits be h, t and u
Let the number be 100h+10t+u
t=5u-3
3*(h+t+u)=2+4h
100u+10t+h+594=100h+10t+u
721
h=7
t=2
u=1
check
2=5*1-3
2=5-3=2 ok
3*(7+2+1)=2+4*7
3*10=2+28
30=30 ok
127+594=721
721=721 ok