*point–slope form*of linear equation.

*y - y*

_{1}= m(x - x_{1})y - (- 4) = - 5(x - (- 9))

y + 4 = -5(x + 9)

y = - 5x - 45 - 4

**y = - 5x - 49**write an equation in slope-intercept form for the line who's slope = -5 and passes through (-9,-4)

Tutors, sign in to answer this question.

y - (- 4) = - 5(x - (- 9))

y + 4 = -5(x + 9)

y = - 5x - 45 - 4

Here is another method of getting the equation of the line that pass through the point ( -9,-4) and has a slope of -5

recall that the slope m = Rise/Run = y2 -y1 / x2 - x1, and (y2-y1)= m (x2-x1)

let the point ( -9,-4) be equivalent to ( x2,y2) that is x2=-9, and y2=-4

Let the point ( x,y) be equivalent to ( x1,x2) that is x = x1, and y=y1 Now substitute into the equation

above above for m = -5 is the given slope

the equation becomes -4-y = -5(-9-x) and -4-y= 45+5x

adding + 4 to to both sides of the equation leads

to - 4+ 4 -y = 45 = 45 + 4 + 5x and -y = 49 + 5x

Mutiplying both sides by -1 leads to -(-y) = -( 49+5x) and y= -5x - 49

This is the same equation of the form y = mx + b where m is the slope = -5 and b is

the y intercept = - 49 at x = 0.

Please note that your choice of the point in the equation does not affect the end result:

Suppose you choose the point (-9,-4) to be ( x1,y1) instead of ( x2,y2)

and the point (x,y) to be ( x2,y2) instead of ( x1,y1)

the equation thus becomes y-(-4) = -5 ( x - (-9)) and y + 4 = -5x - 45

adding -4 to both sides of the equation leads to y+ 4 - 4 = -5x - 45 - 4,

and y = -5x - 49 same as above

Standard equation for a line is **Y = mX + b**. Where **
m** is the slope and **b** is the y intercept. Since you said that the slope is -5, then
**m = -5**. Substituting we now have:

Solving for **b**. We get:

So, our equation is **Y = -5X - 49.**

Already have an account? Log in

By signing up, I agree to Wyzant’s terms of use and privacy policy.

Or

To present the tutors that are the best fit for you, we’ll need your ZIP code.

Your Facebook email address is associated with a Wyzant tutor account. Please use a different email address to create a new student account.

Good news! It looks like you already have an account registered with the email address **you provided**.

It looks like this is your first time here. Welcome!

To present the tutors that are the best fit for you, we’ll need your ZIP code.

Please try again, our system had a problem processing your request.

Rebecca D.

Experienced and Patient Tutor for Math and Reading

$10.75 per 15 min

View Profile >

Alexis G.

All-Subject/Test Prep Tutor, Specializing in Language Instruction

$11.25 per 15 min

View Profile >

Michael B.

Effective Tutor Specializing in Mathematics

$10 per 15 min

View Profile >