Question

A line has a slope of -1/7 and passes through (4, -2) and (p, -1) what is the value of p

Answer 1

Therefore the value of p is -3.

Explanation:

Given a line has a slope of
`-(1)/(7)` and passes through (4,-2)and (p,-1)

The slope of a line which passes through
`(x_1,y_1)` and
`(x_2,y_2)` is

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

Here
`x_1= 4,y_1=-2, x_2=p` and
`y_2= -1`

Therefore the slope of the line which passes through the given points is

`=(-1+2)/(p-4)`

According to the problem,

`(-1+2)/(p-4)= -(1)/(7)`

`\Leftrightarrow (1)/(p-4) =-(1)/(7)`

`\Leftrightarrow p-4=-7`

`\Leftrightarrow p = -7+4`

`\Leftrightarrow p = -3`

Therefore the value of p is -3.