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)

Respuesta :

(-1,3)(1,7)
slope = (7 - 3) / (1 - (-1) = 4/(1 + 1) = 4/2 = 2

y - y1 = m(x - x1)
slope(m) = 2
(-1,3)...x1 = -1 and y1 = 3
now we sub
y - 3 = 2(x -(-1)...not done yet
y - 3 = 2(x + 1) <=== here is one solution

y - y1 = m(x - x1)
slope(m) = 2
(1,7)...x1 = 1 and y1 = 7
now we sub
y - 7 = 2(x - 1) <== here is another solution

but since only one of the answers is in ur answer choices....
ur answer is : y - 7 = 2(x - 1)