+0  
 
0
145
1
avatar

What is the y-intercept form for the two points (0, -1) and (3,-2) if their relationship is proportional?

Guest Oct 26, 2017

Best Answer 

 #1
avatar+7048 
+1

I think you want the slope-intercept form for the equation of a line that passes through these points.

 

slope intercept form is:     y = mx + b     , where  " m "  is the slope and  " b"  is the y-intercept.

 

slope  =  \(\frac{\text{change in y}}{\text{change in x}}\,=\,\frac{y_2-y_1}{x_2-x_1}\,=\,\frac{-2-(-1)}{3-0}\,=\,\frac{-2+1}{3}\,=\,-\frac13\)

 

→    m  =  - \(\frac13\)

 

Since  (0, -1)  is a point on the line, we know that when  x = 0 ,  y = -1  .   So...

 

the y-intercept  =  -1

 

→    b  =  -1

 

So our equation is

 

y  =  - \(\frac13\)x  - 1

hectictar  Oct 26, 2017
edited by hectictar  Oct 26, 2017
Sort: 

1+0 Answers

 #1
avatar+7048 
+1
Best Answer

I think you want the slope-intercept form for the equation of a line that passes through these points.

 

slope intercept form is:     y = mx + b     , where  " m "  is the slope and  " b"  is the y-intercept.

 

slope  =  \(\frac{\text{change in y}}{\text{change in x}}\,=\,\frac{y_2-y_1}{x_2-x_1}\,=\,\frac{-2-(-1)}{3-0}\,=\,\frac{-2+1}{3}\,=\,-\frac13\)

 

→    m  =  - \(\frac13\)

 

Since  (0, -1)  is a point on the line, we know that when  x = 0 ,  y = -1  .   So...

 

the y-intercept  =  -1

 

→    b  =  -1

 

So our equation is

 

y  =  - \(\frac13\)x  - 1

hectictar  Oct 26, 2017
edited by hectictar  Oct 26, 2017

26 Online Users

avatar
New Privacy Policy (May 2018)
We use cookies to personalise content and ads, to provide social media features and to analyse our traffic. We also share information about your use of our site with our social media, advertising and analytics partners.  Privacy Policy