find the standard form of the equation of the line with slope -8/5 and y-intercept -3

Question

8x-15y=5? 5x+8y=-15?

Answer 1

The equation of a line is given by:

 

y = mx + c

where m = slope of line (gradient)    and   c = the y-intercept  (i.e. where the line intercepts the y-axis)

 

So in your case the slope is -8/5 and the y-intercept is -3

 

So,      m = -8/5       and      c = -3  

 

So the equation of the line is:

 

y = mx + c

y = (-8/5)x + (-3)

y = (-8/5)x - 3

 

You can then get this in a different form if you want by multiplying both sides of the equation by 5 to get rid of the fraction:

 

y = (-8/5)x - 3

5y = - 8x - (3x5)

5y = - 8x - 15

 

You can then add 8x to both sides of the equation to get it in the form you wanted:

 

5y = - 8x - 15

5y + 8x = - 8x + 8x - 15

 

5y + 8x = - 15