Question

Give the equation of the line that passes through the points (4,6) and (-2,3)

A. y = 2x + 7
B. y = 1/2x + 7
C. y = 2x + 4
D. y = 1/2x + 4

Answer 1

D. y = 1/2x + 4

Explanation:

Slope: (6-3)/(4--2) = 3/6 = 1/2

y = ½x + c

6 = ½(4) + c

6 = 2 + c

c = 4

y = ½x + 4

Answer 2

y = 1/2x+4

Explanation:

First we find the slope

m = (y2-y1)/(x2-x1)

= (3-6)/(-2-4)

= -3/-6

=1/2

The equation of a line in slope intercept form is

y = mx+b where m is the slope and b is the y intercept

y =1/2x+b

Substitute one of the point into the equation

6 = 1/2(4) +b

6 = 2+b

b=4

y = 1/2x+4