Question

What is the equation in point−slope form of the line passing through (2, 2) and (4, 8)?

A. (y − 2) = 3(x − 2)
B. (y + 2) = 3(x + 2)
C. (y − 8) = −3(x − 4)
D. (y + 8) = −3(x + 4)

Answer 1

y-y1=m(x-x1)
that is equaton of a line passing through the point (x1,y1) and having a slope of m

find slope betweeen given points

slope between (x1,y1) and (x2,y2) is (y2-y1)/(x2-x1)
given (2,2) and (4,8)
slope=(8-2)/(4-2)=6/2=3


a point is (2,2) or (4,8)

slope is m=3

so the equation is

y-2=3(x-2) or
y-8=3(x-4)

the answer is A