Question

Line B passes through points (4, 5) and (2, 9). What is the slope of a line parallel to line B?

A. -2
B. - 1/2
C. 1/2
D. 2

Line B passes through the points (5, 10) and (0, 0). What is the slope of the line perpendicular to line B?

A. -2
B. - 1/2
C. 1/2
D. 2

Answer 1

(4,5), (2,9)
we need to find the slope using the slope formula : (y2 - y1) / (x2 - x1)
now we label ur points..
(4,5)...x1 = 4 and y1 = 5
(2,9)...x2 = 2 and y2 = 9
now we sub into the slope formula and find the slope
slope = (9 - 5) / (2 - 4) = 4/-2 = -2....so ur slope is -2

A parallel line will have the same slope. So ur parallel line also has a slope of -2.

A perpendicular line will have a negative reciprocal slope. To find the negative reciprocal, flip the original slope and change the sign. So our original slope is -2 or -2/1.......flip the slope making it -1/2.....change the sign making it 1/2. Therefore, ur perpendicular line will have a slope of 1/2.