Explanation:
3/4
insert 1st point into y=mx+b
3=m(6)+b
insert 2nd point into y=mx+b
6=m(10)+b
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use system of equations to solve for m and b
b=3-6m
b=6-10m
3-6m=6-10m
4m=3
m=3/4
insert back into the equation
3=(3/4)6+b
3=9/2+b
3-9/2=b
-3/2=b
insert back into y=mx+b
m=slope
b=y-intercept
y=(3/4)x-3/2
slope=3/4
Hope that helps :)