Question

What is the equation of a line, in general form, that passes through point (1, -2) and has a slope of 1/3

3x - y - 7 = 0
x - 3y + 7 = 0
x - 3y - 7 = 0

Answer 1

x-3y-7=0

Explanation:

Given

m=1/3

The standard form of point slop form is:

y=mx+b

To find the value of b, we will put the point in the standard form

So,

`-2=(1)/(3)(1)+b`

Solving for b
`-2=(1)/(3)+b\\-2-(1)/(3)=b\\(-6-1)/(3)=b\\b=(-7)/(3)`

Putting the values of b and m in standard form:

`y=(1)/(3)x+(-7)/(3)\\y=(1)/(3)x-(7)/(3)Multiplying\ both\ sides\ by\ 3\\3y=x-7\\-x+3y+7=0\\Can\ also\ be\ written\ as\\x-3y-7=0`