3 1/6 / 1/3 =
19/6 / 1/3 =
19/6 * 3/1 = 57/6 = 9 1/2 gallons per square foot
Slope of line
m= (y2-y1)/(x2-x1)
=(-4--6)/(6--2)
=2/8
=1/4
Line in two point form
(y-y1)=m(x-x1)
y--2=(1/4)(x-6)
y+2=(1/4)(x-6)
simplify
4(y+2)=x-6 =>
x-4y-14=0
Alternatively, use the slope intercept form:
y--2=(1/4)(x-6) =>
y=(1/4)x - 3/2-2 =>
y=(1/4)x -7/2
Let x = the amount of time that the third person needs to work on the job to add up to one
1 = 1/2 + 1/3 + x
1 - 1/2 - 1/3 = x
To subtract the fractions we need to put them all over a common denominator. Let's use 3*2 = 6 as the denominator; so 1 = 6/6, 1/2 = 3/6, 1/3 = 2/6:
6/6 - 3/6 - 2/6 = x
1/6 = x
The third person must work 1/6 time on the project.