Question

The value of y so that the line through (3, y) and (2, 7) is parallel to the line through (-1, 4) and (0, 6) is

Answer 1

Answer:

for two lines to be parallel, their slopes must be equal

m1 = m2

points are (3, y) and (2, 7) line L1

and. (-1, 4) and (0, 6) line L2

slope of line = (y2 - y1)/(x2 - x1)

slope of L1 = (7 - y)/(2 - 3)

slope of L2 = (6 - 4)/[0 - (-1)] = 2/1 = 2

L1 = L2

ie (7 - y)/-1 = 2

=> (7 - y) = -2

=> - y = -2 - 7

=> - y = -9

=> y = 9