Question

A line passes through the points (1, –6) and (4, 3).

Answer 1

y = 3x - 9

Explanation:

We first need to find the slope (m)

m =
`(y_2-y_1)/(x_2-x_1)` =
`(3 - (-6))/(4-1)` =
`(9)/(3)` = 3

y = mx + b

y = 3x + b

(4, 3)

y = 3x + b

3 = 3(4) + b

3 = 12 + b

-12 -12

-9 = b

(1, –6)

y = 3x + b

-6 = 3(1) + b

-6 = 3 + b

-3 -3

-9 = b

y = 3x - 9

To check: (1, –6)

y = 3x - 9

-6 = 3(1) - 9

-6 = 3 - 9

-6 = -6

Hope this helps!