Question

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

What is the y-intercept of this line?
A.-9
B.-3
C.3
D.9

Answer 1

-9 I believe that's the answr

Answer 2

A. -9

Explanation:

The equation of a line passes through the points
`(x_1, y_1)` and
`(x_2, y_2)` is,

`y-y_1=(y_2-y_1)/(x_2-x_1)(x-x_1)`

Thus, the equation of the line passes through the points (1, –6) and (4, 3) would be,

`y+6=(3+6)/(4-1)(x-1)`

`y+6=(9)/(3)(x-1)`

`y+6=3(x-1)`

`y+6=3x-3`

`\implies 3x-y=9`

For y-intercept, x = 0

3(0) - y = 9

⇒ y = -9

Hence, the y-intercept of the line is -9.

Option 'A' is correct.