Answer:
a. (-12, 14), (6, 2), (-3, 8)
b. yes; R(-12, 14)
Step-by-step explanation:
Points P(-6, 10), Q(0, -6), and R lie on a line, with one of them being the midpoint of the other two. You want to know the possible locations of R, and its location if RQ=√208.
Setup
Point M is the midpoint of AB when ...
M = (A +B)/2
If M and A are given, then B is ...
2M -A = B . . . . . . above equation solved for B
a. Possible locations of R
There are three choices for the location of R.
P is the midpoint
R = 2P -Q = 2(-6, 10) -(0, 6) = (-12, 20-6)
R = (-12, 14)
Q is the midpoint
R = 2Q -P = 2(0, 6) -(-6, 10) = (6, 12 -10)
R = (6, 2)
R is the midpoint
R = (P +Q)/2 = ((-6, 10) +(0, 6))/2 = (-6, 16)/2
R = (-3, 8)
The possible coordinates of R are (-12, 14), (6, 2), (-3, 8).
b. R for RQ=√208
The length of the given segment PQ is ...
d = √((x2 -x1)² +(y2 -y1)²) . . . . . distance formula
d = √((0 -(-6))² +(6 -10)²) = √(6² +(-4)²) = √(36 +16) = √52
This is half the length of RQ, so we must have P as the midpoint of RQ.
This distance information chooses one of the three points found in part (a), R(-12, 14).
