Question

m is the midpoint of AB has coordinates (5, -4), if A has coordinates (6, 1). What are the coordinates of B?

Answer 1

Answer: (4,9)

Step-by-step explanation: We assume a straight line, so y=mx+b.

We can determine slope, m: Change in x is (6-5)=1. Change in y is (1-(-4)) = 5 Slope is (Change in y)/(Change in x) = 5/1, or 5

y=5x+b

Find b for (6,1)

1 = 5*6 + b

b = -29

y = 5x-29

Since A is (6,1) and m is (5,-4) we can calculate y for x=4 (point B)

y = 5(4)-29

y = -9

B is (4,-9)