# linear equation: Find eqn. of line through (3, -7) with ....

#### nikki26

##### New member

Find the equation of the line through the point (3, -7) with slope of -1/4.

I don't know how to start to solve this problem.

#### jacket81

##### Junior Member
Okay, insert the point and the slope in y=mx+b equation.

So, you have -7 = ((-1/4)(3)) + b.

Now, you can find b.

Add ((1/4)3) to both sides of equation, giving you -7 + ((1/4)3) = b, or b = -7 + (3/4) = (-28/4)+(3/4) = (-25/4).

So, the equation is y=((-1/4)x) - (25/4)

#### tkhunny

##### Moderator
Staff member
Re: linear equation: Find eqn. of line through (3, -7) with

nikki26 said:
Find the equation of the line through the point (3, -7) with slope of -1/4.
I don't know how to start to solve this problem.
I absolutely do not believe this. It simply cannot be the case. Did the problem just fall out of the sky one day? You were walking along the road and you tripped over it? OK -- If you've been out sick, maybe I can believe it.

Somewhere, some time, somehow, you must have encountered a few basics. Perhaps these:

Slope-Intercept Form: $$\displaystyle y = m*x + b$$

Point-Slope Form: $$\displaystyle (y-y_{0}) = m*(x-x_{0})$$

You are given the information for the Point-Slope Form, a point and the slope.

#### jonboy

##### Full Member
Re: linear equation: Find eqn. of line through (3, -7) with

tkhunny said:
nikki26 said:
Find the equation of the line through the point (3, -7) with slope of -1/4.
I don't know how to start to solve this problem.
I absolutely do not believe this. It simply cannot be the case. Did the problem just fall out of the sky one day? You were walking along the road and you tripped over it? OK -- If you've been out sick, maybe I can believe it.

Somewhere, some time, somehow, you must have encountered a few basics. Perhaps these:

Slope-Intercept Form: $$\displaystyle y = m*x + b$$

Point-Slope Form: $$\displaystyle (y-y_{0}) = m*(x-x_{0})$$

You are given the information for the Point-Slope Form, a point and the slope.
You could have also heard of Standard Form for a line as well: $$\displaystyle \L \;ax\,+\,by\,=\,c$$