Let
x---------> time it takes the person a to paint the house
y---------> time it takes the person b to paint the house
we know that
x=y/6
x+y=9
using a graph tool
see the attached figure
the solution is
x=1.286-------> x=1.3 days
y=7.714-------> y=7.7 days
the answer is
time it takes the person a to paint the house----> 1.3 days
time it takes the person a to paint the house----> 7.7 days
