Answer:
x = -1
Step-by-step explanation:
Because the line passes through two points that both have the same x value, this means the line is vertical, and the slope is undefined.
So the equation of the line is x = -1.
Answer:
Sharon bought a necklace with 90% blue beads.
Step-by-step explanation:
We are given that Sharon's necklace has 80 beads. We are also given that of those 80 beads, 72 of them are blue.
Therefore, we can set up a ratio of blue beads to total beads in order to find out the relationship.

Then, using the fraction we receive as a result, we can convert this to a decimal.

After we complete this calculation, we can multiply our decimal by 100 in order to obtain the relationship in percentage form.

Of the 80 beads, 90% were blue beads.
I think you mean "a set of three points". What I would do is take one point, find the slope from that point to another one, and then find the slope from the same starting point to the third one. If the (absolute values of the) slopes from the same starting point to each of the others are equal, then the three points are collinear.