Answer:
The steps to construct a a line parallel to another line from a point includes
1) From the given line draw a transversal through the point
2) With the compass, copy the angle formed between the transversal and the given line to the point P
3) Draw a line through the intersection of the arcs of the angle construction to get the parallel line through the point P
Step-by-step explanation:
Divide the number of people selected by the total number of people.
90/500 = .18
This means that 18% of the customers were selected for the survey.
If the probability is the same on Saturday, then we can multiply the expected customers by our .18
700 x .18 = 126
126 should be selected for the survey on Saturday.
When x=-1:

Ok that gives us a little more information.
If we implicitly differentiate with respect to t, from the very start, then we can apply our product rule, ya?

The right side is zero, derivative of a constant is zero.
Where x' is dx/dt and y' is dy/dt.
From here, plug in all the stuff you know:
y' = -3
x = -1
y = 4
and solve for x'.
Hope that helps!