Question

What equation in slope-intercept form represents the line that passes

through the points (3,-2) and (1, -3)?

Answer 1

2y = x - 7

Explanation:

The general equation of the line is;

y = mx + b

where m is the slope and b is the y-intercept

To get the slope, we use the slope formula

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

(x1, y1) = (3,-2)

(x2,y2) = (1,-3)

m = (-3+2)/(1-3) = -1/-2 = 1/2

So we have the equation as;

y = x/2 + b

Multiply through by 2

2y = x + 2b

To get the y-intercept value, we substitute any of the points

Let us use the first point

While 3 will go for x , -2 will go for y; thus we have;

2(-2) = 3 + 2b

-4 = 3 + 2b

2b = -4-3

2b = -7

b = -7/2

So the equation is;

2y = x -7