Question

Write an equation of the line that passes through the point (4, –5) with slope 2.

answers:
A. y−4=2(x+5)
B. y+5=−2(x−4)
C. y−4=−2(x+5)
D. y+5=2(x−4)

Answer 1

D. y+5=2(x−4)

Explanation:

The point-slope form of the equation of a line is useful for writing an equation for a line through a given point with a given slope.

Point-slope form

The point-slope form of the equation of a line is ...

y -k = m(x -h) . . . . . . line through point (h, k) with slope m

Application

We want a line through point (h, k) = (4, -5) with slope m = 2. Putting these numbers into the form gives ...

y -(-5) = 2(x -4)

y +5 = 2(x -4) . . . . . . simplifying the signs