Posted by Alana on Monday, January 23, 2012 at 8:10pm.
Lines A and B are perpendicular and have the same xintercept. The equation of line A is x+2y4=0. Determine the yintercept of line B.

Math  Reiny, Monday, January 23, 2012 at 9:44pm
slope of given line = 1/2
so slope of perpendicular line = +2
xintercept of given line, let y = 0
xintercept is (4,0)
so new line: slope = 2, point (4,0) on it
y = 0 = 2(x4)
y = 2x  8
yintercept of new line is 8 or (0, 8)