Question

What is the equation in point-slope form of the line passing through (1, 9) and (-1, 11)?

A. y + 9 = -(x - 1)
B. y - 9 = 1(x + 1)
C. y + 9 = 1(x + 1)
D. y - 9 = -(x - 1)

Answer 1

first we need to find the slope by using the slope formula :
slope(m) = (y2 - y1) / (x2 - x1)
(1,9) x1 = 1 and y1 = 9
(-1,11) x2 = -1 and y2 = 11
now we sub
slope(m) = (11 - 9) / (-1-1)
m = 2/-2 = -1 <== slope is -1

now we will use point slope formula :
y - y1 = m(x - x1)
(slope)m) = -1
(1,9) x1 = 1 and y1 = 9
now we sub
y - 9 = -1(x - 1) or y - 9 = -(x - 1)

any questions ?

Answer 2

so it can equal Y= -x+10

Answer 3

lol @kelliegirl33 i was about to hit post when yours came up so i just deleted mine lol

Answer 4

therefore the answer would be A