Question

A line passes through the points (6, 10) and (4, -2). What is the equation of the line

Answer 1

y = -1/6 x + 11

Explanation:

In order to write an equation of a line you need slope (m) and y-intercept (b) or where the graph grosses the y- axis. since you are given two points (6, 10) and (4, -2). Slope when given two points is (y - y) / (x - x)

so (-2 - 10) / (6 - 4) = 6 / - 1 =- 6

use the equation y = mx + b and substitute either point (6, 10) or (4, -2) as a replacement for x and y respectively. (I chose (6, 10) because they are positive numbers. Substituting x = 6 and y = 10 and m = -6 into y = mx + b

10 = -6(6) + b

10 = -36 + b

b = 46 (add -36 to both sides)

so our equation: y = -6x + 46 :-)

Answer 2

y = 6x - 26

Explanation:

1. find slope: (y₂ - y₁) / (x₂ - x₁)

(-2 - 10) / (4 - 6) = -12 / -2 = 6

basic equation: y = 6x + b

2. plug in (x,y) value using one set of coordinates.

10 = 6(6) + b

10 = 36 + b

b = 10 - 36

b = -26

3. plug b in to find full equation.

y = 6x -26