Answer:
x = - 11
Step-by-step explanation:
y = 15 is a horizontal line parallel to the x- axis
a perpendicular line must therefore be a vertical line parallel to the y- axis with equation
x = c
where c is the value of the x- coordinates the line passes through.
the line passes through (- 11, - 1 ) with x- coordinate of - 11 , then
x = - 11 ← equation of perpendicular line
I set it up as a ratio with hours on the top and the fraction of the job on the bottom. It looks like this: 5/(2/3) / x/1, because 1 is the whole job if 2/3 is only a fraction of it. Cross multiplying gives you 2/3x = 5. Solving for x gives you that it will take 7.5 hours to complete a whole job if it takes 5 hours to complete 2/3 of it.