What is the equation in point-slope form of the line passing through (–1, 3) and (1, 7)?

y – 7 = 4(x – 1)

y – 7 = 2(x – 1)

y – 3 = 2(x – 1)

y – 3 = 4(x + 1)

Question

What is the equation in point-slope form of the line passing through (–1, 3) and (1, 7)?

 y – 7 = 4(x – 1)

 y – 7 = 2(x – 1)

 y – 3 = 2(x – 1)

 y – 3 = 4(x + 1)

blurbendy · Answer

you need to find the slope first.

slope = (y2 - y1) / (x2 - x1)

where y2 = 7
y1 = 3
x2 = 1
x1 = -1

anonymous · Answer

5/2

anonymous · Answer

oh no its 2

blurbendy · Answer

7 -3 = 4
1 + 1 = 2
slope = 2, yes

hero · Answer

So eliminate two of your answer choices.

blurbendy · Answer

now use the formula:

y - y1 = 4(x - x1)

use either (-1, 3) or (1,7) for x1 and y1, but do not combine them

hero · Answer

Its between:

 y – 7 = 2(x – 1)
or
 y – 3 = 2(x – 1)

blurbendy · Answer

that 4 should be a 2, sorry

hero · Answer

@blurbendy, I thought we agreed the slope was 2

anonymous · Answer

is it y-7 = 2(x-1)?

blurbendy · Answer

yes, now isolate y

anonymous · Answer

thats all i need, thank you!

blurbendy · Answer

actually, you dont need to.  youre done!